[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"project-11700":3},{"id":4,"name":5,"fullName":6,"owner":7,"repo":5,"description":8,"homepage":9,"htmlUrl":10,"language":11,"languages":9,"totalLinesOfCode":9,"stars":12,"forks":13,"watchers":14,"openIssues":15,"contributorsCount":9,"subscribersCount":15,"size":15,"stars1d":16,"stars7d":17,"stars30d":18,"stars90d":15,"forks30d":15,"starsTrendScore":19,"compositeScore":20,"rankGlobal":9,"rankLanguage":9,"license":9,"archived":21,"fork":21,"defaultBranch":22,"hasWiki":21,"hasPages":21,"topics":23,"createdAt":9,"pushedAt":9,"updatedAt":38,"readmeContent":39,"aiSummary":40,"trendingCount":15,"starSnapshotCount":15,"syncStatus":41,"lastSyncTime":42,"discoverSource":43},11700,"LeetCode-Solutions","kamyu104\u002FLeetCode-Solutions","kamyu104","🏋️ Python \u002F Modern C++ Solutions of All 3958 LeetCode Problems (Weekly Update)",null,"https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions","C++",5859,1802,167,0,27,68,456,81,40.77,false,"main",[24,25,26,27,28,29,30,31,32,33,34,35,36,37],"leetcode","python","cpp","algorithm","data-structure","cpp11","leetcode-solutions","interview-questions","interview-preparation","interview-practice","leetcode-cpp","modern-cpp","leetcode-python","algorithms","2026-06-12 02:02:33","# [LeetCode](https:\u002F\u002Fleetcode.com\u002Fproblemset\u002Fall\u002F)\n\n![Language](https:\u002F\u002Fimg.shields.io\u002Fbadge\u002Flanguage-Python%20%2F%20Modern%20C++-orange.svg) \n[![License](https:\u002F\u002Fimg.shields.io\u002Fbadge\u002Flicense-MIT-blue.svg)](.\u002FLICENSE.md) \n![Update](https:\u002F\u002Fimg.shields.io\u002Fbadge\u002Fupdate-weekly-green.svg) \n![Progress](https:\u002F\u002Fimg.shields.io\u002Fbadge\u002Fprogress-3928%20%2F%203928-ff69b4.svg) \n[![SayThanks](https:\u002F\u002Fimg.shields.io\u002Fbadge\u002Fsay-thanks-ff69f4.svg)](https:\u002F\u002Fsaythanks.io\u002Fto\u002Fkamyu104) \n![Visitors](https:\u002F\u002Fvisitor-badge.laobi.icu\u002Fbadge?page_id=kamyu104.leetcode.solutions)\n\n* R.I.P. to my old Leetcode repository, where there were `5.7k+` stars and `2.2k+` forks (ever the top 3 in the field).\n* Since free questions may be even mistakenly taken down by some companies, only solutions will be post on now.\n* There are new LeetCode questions every week. I'll keep updating for full summary and better solutions.\n* For more problem solutions, you can see my [LintCode](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLintCode), [GoogleKickStart](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FGoogleKickStart-2022), [GoogleCodeJamIO](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FGoogleCodeJamIO-2022) repositories.\n* For more challenging problem solutions, you can also see my [GoogleCodeJam](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FGoogleCodeJam-Farewell-Rounds), [MetaHackerCup](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FMetaHackerCup-2025) repositories.\n* Hope you enjoy the journey of learning data structures and algorithms.\n* Notes: \"🔒\" means your subscription of [LeetCode premium membership](https:\u002F\u002Fleetcode.com\u002Fsubscribe\u002F) is required for reading the question.\n\n## Solutions\n- [0001 - 1000](.\u002F0001-1000.md)\n- [1001 - 2000](.\u002F1001-2000.md)\n- [2001 - 3000](.\u002F2001-3000.md)\n- [3001 - Latest](.\u002FREADME.md)\n\n## Algorithms\n\n* [Bit Manipulation](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#bit-manipulation)\n* [Array](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#array)\n* [String](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#string)\n* [Linked List](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#linked-list)\n* [Stack](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#stack)\n* [Queue](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#queue)\n* [Binary Heap](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#binary-heap)\n* [Tree](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#tree)\n* [Hash Table](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#hash-table)\n* [Math](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#math)\n* [Sort](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#sort)\n* [Two Pointers](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#two-pointers)\n* [Recursion](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#recursion)\n* [Binary Search](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#binary-search)\n* [Binary Search Tree](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#binary-search-tree)\n* [Breadth-First Search](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#breadth-first-search)\n* [Depth-First Search](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#depth-first-search)\n* [Backtracking](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#backtracking)\n* [Dynamic Programming](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#dynamic-programming)\n* [Greedy](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#greedy)\n* [Graph](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#graph)\n* [Geometry](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#geometry)\n* [Simulation](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#simulation)\n* [Constructive Algorithms](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#constructive-algorithms)\n* [Design](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#design)\n\n## JavaScript\n\n* [JS](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#js)\n\n## Database\n\n* [SQL](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#sql)\n\n\n## Pandas\n\n* [PD](https:\u002F\u002Fgithub.com\u002Fkamyu104\u002FLeetCode-Solutions#pd)\n\n## Reference\n\n* [Links](.\u002FREFERENCE.md)\n\n## Bit Manipulation\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3064 | [Guess the Number Using Bitwise Questions I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fguess-the-number-using-bitwise-questions-i\u002F) | [C++](.\u002FC++\u002Fguess-the-number-using-bitwise-questions-i.cpp) [Python](.\u002FPython\u002Fguess-the-number-using-bitwise-questions-i.py) | _O(logn)_ | _O(1)_ | Medium |🔒| Bit Manipulation\n3094 | [Guess the Number Using Bitwise Questions II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fguess-the-number-using-bitwise-questions-ii\u002F) | [C++](.\u002FC++\u002Fguess-the-number-using-bitwise-questions-ii.cpp) [Python](.\u002FPython\u002Fguess-the-number-using-bitwise-questions-ii.py) | _O(logr)_ | _O(1)_ | Medium |🔒| Bit Manipulation\n3125 | [Maximum Number That Makes Result of Bitwise AND Zero](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-number-that-makes-result-of-bitwise-and-zero\u002F) | [C++](.\u002FC++\u002Fmaximum-number-that-makes-result-of-bitwise-and-zero.cpp) [Python](.\u002FPython\u002Fmaximum-number-that-makes-result-of-bitwise-and-zero.py) | _O(1)_ | _O(1)_ | Medium |🔒| Bit Manipulation\n3133 | [Minimum Array End](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-array-end\u002F) | [C++](.\u002FC++\u002Fminimum-array-end.cpp) [Python](.\u002FPython\u002Fminimum-array-end.py) | _O(logn)_ | _O(1)_ | Medium | | Bit Manipulation\n3199 | [Count Triplets with Even XOR Set Bits I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-triplets-with-even-xor-set-bits-i\u002F) | [C++](.\u002FC++\u002Fcount-triplets-with-even-xor-set-bits-i.cpp) [Python](.\u002FPython\u002Fcount-triplets-with-even-xor-set-bits-i.py) | _O(nlogr)_ | _O(1)_ | Easy | 🔒 | Brute Force, Bit Manipulation, Parity\n3215 | [Count Triplets with Even XOR Set Bits II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-triplets-with-even-xor-set-bits-ii\u002F) | [C++](.\u002FC++\u002Fcount-triplets-with-even-xor-set-bits-ii.cpp) [Python](.\u002FPython\u002Fcount-triplets-with-even-xor-set-bits-ii.py) | _O(nlogr)_ | _O(1)_ | Medium | 🔒 | Bit Manipulation, Parity\n3226 | [Number of Bit Changes to Make Two Integers Equal](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-bit-changes-to-make-two-integers-equal\u002F) | [C++](.\u002FC++\u002Fnumber-of-bit-changes-to-make-two-integers-equal.cpp) [Python](.\u002FPython\u002Fnumber-of-bit-changes-to-make-two-integers-equal.py) | _O(logn)_ | _O(1)_ | Easy | | Bit Manipulation\n3289 | [The Two Sneaky Numbers of Digitville](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fthe-two-sneaky-numbers-of-digitville\u002F) | [C++](.\u002FC++\u002Fthe-two-sneaky-numbers-of-digitville.cpp) [Python](.\u002FPython\u002Fthe-two-sneaky-numbers-of-digitville.py) | _O(n)_ | _O(1)_ | Easy | | Bit Manipulation\n3304 | [Find the K-th Character in String Game I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-k-th-character-in-string-game-i\u002F) | [C++](.\u002FC++\u002Ffind-the-k-th-character-in-string-game-i.cpp) [Python](.\u002FPython\u002Ffind-the-k-th-character-in-string-game-i.py) | _O(n)_ | _O(1)_ | Easy | | Bitmasks\n3307| [Find the K-th Character in String Game II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-k-th-character-in-string-game-ii\u002F) | [C++](.\u002FC++\u002Ffind-the-k-th-character-in-string-game-ii.cpp) [Python](.\u002FPython\u002Ffind-the-k-th-character-in-string-game-ii.py) | _O(1)_ | _O(1)_ | Hard | | Bitmasks\n3314 | [Construct the Minimum Bitwise Array I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconstruct-the-minimum-bitwise-array-i\u002F) | [C++](.\u002FC++\u002Fconstruct-the-minimum-bitwise-array-i.cpp) [Python](.\u002FPython\u002Fconstruct-the-minimum-bitwise-array-i.py) | _O(n)_ | _O(1)_ | Easy | | Bit Manipulation\n3315 | [Construct the Minimum Bitwise Array II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconstruct-the-minimum-bitwise-array-ii\u002F) | [C++](.\u002FC++\u002Fconstruct-the-minimum-bitwise-array-ii.cpp) [Python](.\u002FPython\u002Fconstruct-the-minimum-bitwise-array-ii.py) | _O(n)_ | _O(1)_ | Medium | | Bit Manipulation\n3344 | [Maximum Sized Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-sized-array\u002F) | [C++](.\u002FC++\u002Fmaximum-sized-array.cpp) [Python](.\u002FPython\u002Fmaximum-sized-array.py) | precompute: O(max_s^(1\u002F5) * log(max_s))\u003Cbr>runtime: O(log(max_s)) | _O(max_s^(1\u002F5))_ | Medium | 🔒 | Precompute, Bitmasks, Combinatorics, Binary Search\n3370 | [Smallest Number With All Set Bits](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsmallest-number-with-all-set-bits\u002F) | [C++](.\u002FC++\u002Fsmallest-number-with-all-set-bits.cpp) [Python](.\u002FPython\u002Fsmallest-number-with-all-set-bits.py) | _O(1)_ | _O(1)_ | Easy | | Bit Manipulation\n3566 | [Partition Array into Two Equal Product Subsets](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fpartition-array-into-two-equal-product-subsets\u002F) | [C++](.\u002FC++\u002Fpartition-array-into-two-equal-product-subsets.cpp) [Python](.\u002FPython\u002Fpartition-array-into-two-equal-product-subsets.py) | _O(n * 2^n)_ | _O(1)_ | Medium | | Bitmasks\n3632 | [Subarrays with XOR at Least K](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsubarrays-with-xor-at-least-k\u002F) | [C++](.\u002FC++\u002Fsubarrays-with-xor-at-least-k.cpp) [Python](.\u002FPython\u002Fsubarrays-with-xor-at-least-k.py) | _O(nlogr)_ | _O(t)_ | Hard | 🔒 | Bitmasks, Prefix Sum, Trie\n3646 | [Next Special Palindrome Number](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnext-special-palindrome-number\u002F) | [C++](.\u002FC++\u002Fnext-special-palindrome-number.cpp) [Python](.\u002FPython\u002Fnext-special-palindrome-number.py) | precompute: _O(9 * 2^9 + 16 * p + plogp)_\u003Cbr>runtime: _O(logp)_ | _O(p)_ | Hard | | Precompute, Bitmasks, Sort, Binary Search\n3702 | [Longest Subsequence With Non-Zero Bitwise XOR](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-subsequence-with-non-zero-bitwise-xor\u002F) | [C++](.\u002FC++\u002Flongest-subsequence-with-non-zero-bitwise-xor.cpp) [Python](.\u002FPython\u002Flongest-subsequence-with-non-zero-bitwise-xor.py) | _O(n)_ | _O(1)_ | Medium | | Bitmasks\n3750 | [Minimum Number of Flips to Reverse Binary String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-number-of-flips-to-reverse-binary-string\u002F) | [C++](.\u002FC++\u002Fminimum-number-of-flips-to-reverse-binary-string.cpp) [Python](.\u002FPython\u002Fminimum-number-of-flips-to-reverse-binary-string.py) | _O(logn)_ | _O(1)_ | Easy | | Bitmasks\n3766 | [Minimum Operations to Make Binary Palindrome](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-operations-to-make-binary-palindrome\u002F) | [C++](.\u002FC++\u002Fminimum-operations-to-make-binary-palindrome.cpp) [Python](.\u002FPython\u002Fminimum-operations-to-make-binary-palindrome.py) | precompute: _O(sqrt(r) * logr)_\u003Cbr>runtime: _O(r)_ | _O(r)_ | Medium | | Precompute, Bitmasks, Two Pointers\n3769 | [Sort Integers by Binary Reflection](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsort-integers-by-binary-reflection\u002F) | [C++](.\u002FC++\u002Fsort-integers-by-binary-reflection.cpp) [Python](.\u002FPython\u002Fsort-integers-by-binary-reflection.py) | _O(nlogr + nlogn)_ | _O(n)_ | Easy | | Sort, Bitmasks\n3782 | [Last Remaining Integer After Alternating Deletion Operations](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flast-remaining-integer-after-alternating-deletion-operations\u002F) | [C++](.\u002FC++\u002Flast-remaining-integer-after-alternating-deletion-operations.cpp) [Python](.\u002FPython\u002Flast-remaining-integer-after-alternating-deletion-operations.py) | _O(1)_ | _O(1)_ | Hard | | Bitmasks, Simulation\n3827 | [Count Monobit Integers](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-monobit-integers\u002F) | [C++](.\u002FC++\u002Fcount-monobit-integers.cpp) [Python](.\u002FPython\u002Fcount-monobit-integers.py) | _O(logn)_ | _O(1)_ | Easy | | Bitmasks\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## Array\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3009 | [Maximum Number of Intersections on the Chart](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-number-of-intersections-on-the-chart\u002F) | [C++](.\u002FC++\u002Fmaximum-number-of-intersections-on-the-chart.cpp) [Python](.\u002FPython\u002Fmaximum-number-of-intersections-on-the-chart.py) | _O(nlogn)_ | _O(n)_ | Hard | 🔒 | Sort, Line Sweep, Coordinate Compression\n3010 | [Divide an Array Into Subarrays With Minimum Cost I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fdivide-an-array-into-subarrays-with-minimum-cost-i\u002F) | [C++](.\u002FC++\u002Fdivide-an-array-into-subarrays-with-minimum-cost-i.cpp) [Python](.\u002FPython\u002Fdivide-an-array-into-subarrays-with-minimum-cost-i.py) | _O(n)_ | _O(1)_ | Easy | | Array, Quick Select\n3015 | [Count the Number of Houses at a Certain Distance I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-the-number-of-houses-at-a-certain-distance-i\u002F) | [C++](.\u002FC++\u002Fcount-the-number-of-houses-at-a-certain-distance-i.cpp) [Python](.\u002FPython\u002Fcount-the-number-of-houses-at-a-certain-distance-i.py) | _O(n)_   | _O(n)_        | Medium         | | Math, Prefix Sum, Difference Array\n3017 | [Count the Number of Houses at a Certain Distance II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-the-number-of-houses-at-a-certain-distance-ii\u002F) | [C++](.\u002FC++\u002Fcount-the-number-of-houses-at-a-certain-distance-ii.cpp) [Python](.\u002FPython\u002Fcount-the-number-of-houses-at-a-certain-distance-ii.py) | _O(n)_   | _O(1)_        | Hard         | | Math, Prefix Sum, Difference Array\n3026 | [Maximum Good Subarray Sum](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-good-subarray-sum\u002F) | [C++](.\u002FC++\u002Fmaximum-good-subarray-sum.cpp) [Python](.\u002FPython\u002Fmaximum-good-subarray-sum.py) | _O(n)_ | _O(n)_ | Medium | | Prefix Sum\n3028 | [Ant on the Boundary](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fant-on-the-boundary\u002F) | [C++](.\u002FC++\u002Fant-on-the-boundary.cpp) [Python](.\u002FPython\u002Fant-on-the-boundary.py) | _O(n)_ | _O(1)_ | Easy | | Prefix Sum\n3030 | [Find the Grid of Region Average](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-grid-of-region-average\u002F) | [C++](.\u002FC++\u002Ffind-the-grid-of-region-average.cpp) [Python](.\u002FPython\u002Ffind-the-grid-of-region-average.py) | _O(m * n)_ | _O(m * n)_ | Medium | | Array\n3033 | [Modify the Matrix](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmodify-the-matrix\u002F) | [C++](.\u002FC++\u002Fmodify-the-matrix.cpp) [Python](.\u002FPython\u002Fmodify-the-matrix.py) | _O(m * n)_ | _O(1)_ | Easy | | Array\n3038 | [Maximum Number of Operations With the Same Score I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-number-of-operations-with-the-same-score-i\u002F) | [C++](.\u002FC++\u002Fmaximum-number-of-operations-with-the-same-score-i.cpp) [Python](.\u002FPython\u002Fmaximum-number-of-operations-with-the-same-score-i.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3065 | [Minimum Operations to Exceed Threshold Value I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-operations-to-exceed-threshold-value-i\u002F) | [C++](.\u002FC++\u002Fminimum-operations-to-exceed-threshold-value-i.cpp) [Python](.\u002FPython\u002Fminimum-operations-to-exceed-threshold-value-i.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3069 | [Distribute Elements Into Two Arrays I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fdistribute-elements-into-two-arrays-i\u002F) | [C++](.\u002FC++\u002Fdistribute-elements-into-two-arrays-i.cpp) [Python](.\u002FPython\u002Fdistribute-elements-into-two-arrays-i.py) | _O(n)_ | _O(n)_ | Easy | | Array\n3070 | [Count Submatrices with Top-Left Element and Sum Less Than k](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-submatrices-with-top-left-element-and-sum-less-than-k\u002F) | [C++](.\u002FC++\u002Fcount-submatrices-with-top-left-element-and-sum-less-than-k.cpp) [Python](.\u002FPython\u002Fcount-submatrices-with-top-left-element-and-sum-less-than-k.py) | _O(n * m)_ | _O(1)_ | Medium | | Array, Prefix Sum\n3071 | [Minimum Operations to Write the Letter Y on a Grid](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-operations-to-write-the-letter-y-on-a-grid\u002F) | [C++](.\u002FC++\u002Fminimum-operations-to-write-the-letter-y-on-a-grid.cpp) [Python](.\u002FPython\u002Fminimum-operations-to-write-the-letter-y-on-a-grid.py) | _O(n^2)_ | _O(1)_ | Medium | | Array\n3079 | [Find the Sum of Encrypted Integers](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-sum-of-encrypted-integers\u002F) | [C++](.\u002FC++\u002Ffind-the-sum-of-encrypted-integers.cpp) [Python](.\u002FPython\u002Ffind-the-sum-of-encrypted-integers.py) | _O(nlogr)_ | _O(1)_ | Easy | | Array\n3096 | [Minimum Levels to Gain More Points](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-levels-to-gain-more-points\u002F) | [C++](.\u002FC++\u002Fminimum-levels-to-gain-more-points.cpp) [Python](.\u002FPython\u002Fminimum-levels-to-gain-more-points.py) | _O(n)_ | _O(n)_ | Medium | | Prefix Sum\n3105 | [Longest Strictly Increasing or Strictly Decreasing Subarray](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-strictly-increasing-or-strictly-decreasing-subarray\u002F) | [C++](.\u002FC++\u002Flongest-strictly-increasing-or-strictly-decreasing-subarray.cpp) [Python](.\u002FPython\u002Flongest-strictly-increasing-or-strictly-decreasing-subarray.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3127 | [Make a Square with the Same Color](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmake-a-square-with-the-same-color\u002F) | [C++](.\u002FC++\u002Fmake-a-square-with-the-same-color.cpp) [Python](.\u002FPython\u002Fmake-a-square-with-the-same-color.py) | _O((n - w + 1)^2 * w^2)_ | _O(1)_ | Easy | | Array\n3131 | [Find the Integer Added to Array I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-integer-added-to-array-i\u002F) | [C++](.\u002FC++\u002Ffind-the-integer-added-to-array-i.cpp) [Python](.\u002FPython\u002Ffind-the-integer-added-to-array-i.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3142 | [Check if Grid Satisfies Conditions](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcheck-if-grid-satisfies-conditions\u002F) | [C++](.\u002FC++\u002Fcheck-if-grid-satisfies-conditions.cpp) [Python](.\u002FPython\u002Fcheck-if-grid-satisfies-conditions.py) | _O(m * n)_ | _O(1)_ | Easy | | Array\n3147 | [Taking Maximum Energy From the Mystic Dungeon](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ftaking-maximum-energy-from-the-mystic-dungeon\u002F) | [C++](.\u002FC++\u002Ftaking-maximum-energy-from-the-mystic-dungeon.cpp) [Python](.\u002FPython\u002Ftaking-maximum-energy-from-the-mystic-dungeon.py) | _O(n)_ | _O(1)_ | Medium | | Array\n3151 | [Special Array I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fspecial-array-i\u002F) | [C++](.\u002FC++\u002Fspecial-array-i.cpp) [Python](.\u002FPython\u002Fspecial-array-i.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3152 | [Special Array II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fspecial-array-ii\u002F) | [C++](.\u002FC++\u002Fspecial-array-ii.cpp) [Python](.\u002FPython\u002Fspecial-array-ii.py) | _O(n + q)_ | _O(n)_ | Medium | | Prefix Sum\n3153 | [Sum of Digit Differences of All Pairs](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsum-of-digit-differences-of-all-pairs\u002F) | [C++](.\u002FC++\u002Fsum-of-digit-differences-of-all-pairs.cpp) [Python](.\u002FPython\u002Fsum-of-digit-differences-of-all-pairs.py) | _O(nlogr)_ | _O(10 * logr)_ | Medium | | Prefix Sum\n3159 | [Find Occurrences of an Element in an Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-occurrences-of-an-element-in-an-array\u002F) | [C++](.\u002FC++\u002Ffind-occurrences-of-an-element-in-an-array.cpp) [Python](.\u002FPython\u002Ffind-occurrences-of-an-element-in-an-array.py) | _O(n + q)_ | _O(n)_ | Medium | | Array\n3173 | [Bitwise OR of Adjacent Elements](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fbitwise-or-of-adjacent-elements\u002F) | [C++](.\u002FC++\u002Fbitwise-or-of-adjacent-elements.cpp) [Python](.\u002FPython\u002Fbitwise-or-of-adjacent-elements.py) | _O(n)_ | _O(1)_ | Easy | 🔒 | Array\n3187 | [Peaks in Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fpeaks-in-array\u002F) | [C++](.\u002FC++\u002Fpeaks-in-array.cpp) [Python](.\u002FPython\u002Fpeaks-in-array.py) | _O(n + qlogn)_ | _O(n)_ | Hard | | BIT, Fenwick Tree\n3195 | [Find the Minimum Area to Cover All Ones I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-minimum-area-to-cover-all-ones-i\u002F) | [C++](.\u002FC++\u002Ffind-the-minimum-area-to-cover-all-ones-i.cpp) [Python](.\u002FPython\u002Ffind-the-minimum-area-to-cover-all-ones-i.py) | _O(n * m)_ | _O(1)_ | Medium | | Array\n3224 | [Minimum Array Changes to Make Differences Equal](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-array-changes-to-make-differences-equal\u002F) | [C++](.\u002FC++\u002Fminimum-array-changes-to-make-differences-equal.cpp) [Python](.\u002FPython\u002Fminimum-array-changes-to-make-differences-equal.py) | _O(n + k)_   | _O(k)_        | Medium         | | Prefix Sum, Difference Array\n3279 | [Maximum Total Area Occupied by Pistons](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-total-area-occupied-by-pistons\u002F) | [C++](.\u002FC++\u002Fmaximum-total-area-occupied-by-pistons.cpp) [Python](.\u002FPython\u002Fmaximum-total-area-occupied-by-pistons.py) | _O(h)_ | _O(h)_ | Hard | 🔒 | Line Sweep, Difference Array\n3285 | [Find Indices of Stable Mountains](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-indices-of-stable-mountains\u002F) | [C++](.\u002FC++\u002Ffind-indices-of-stable-mountains.cpp) [Python](.\u002FPython\u002Ffind-indices-of-stable-mountains.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3300 | [Minimum Element After Replacement With Digit Sum](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-element-after-replacement-with-digit-sum\u002F) | [C++](.\u002FC++\u002Fminimum-element-after-replacement-with-digit-sum.cpp) [Python](.\u002FPython\u002Fminimum-element-after-replacement-with-digit-sum.py) | _O(nlogr)_ | _O(1)_ | Easy | | Array\n3330 | [Find the Original Typed String I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-original-typed-string-i\u002F) | [C++](.\u002FC++\u002Ffind-the-original-typed-string-i.cpp) [Python](.\u002FPython\u002Ffind-the-original-typed-string-i.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3334 | [Find the Maximum Factor Score of Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-maximum-factor-score-of-array\u002F) | [C++](.\u002FC++\u002Ffind-the-maximum-factor-score-of-array.cpp) [Python](.\u002FPython\u002Ffind-the-maximum-factor-score-of-array.py) | _O(nlogr)_ | _O(n)_ | Medium | | Prefix Sum\n3349 | [Adjacent Increasing Subarrays Detection I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fadjacent-increasing-subarrays-detection-i\u002F) | [C++](.\u002FC++\u002Fadjacent-increasing-subarrays-detection-i.cpp) [Python](.\u002FPython\u002Fadjacent-increasing-subarrays-detection-i.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3350 | [Adjacent Increasing Subarrays Detection II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fadjacent-increasing-subarrays-detection-ii\u002F) | [C++](.\u002FC++\u002Fadjacent-increasing-subarrays-detection-ii.cpp) [Python](.\u002FPython\u002Fadjacent-increasing-subarrays-detection-ii.py) | _O(n)_ | _O(1)_ | Medium | | Array\n3353 | [Minimum Total Operations](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-total-operations\u002F) | [C++](.\u002FC++\u002Fminimum-total-operations.cpp) [Python](.\u002FPython\u002Fminimum-total-operations.py) | _O(n)_   | _O(1)_        | Easy         | 🔒 | Array\n3354 | [Make Array Elements Equal to Zero](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmake-array-elements-equal-to-zero\u002F) | [C++](.\u002FC++\u002Fmake-array-elements-equal-to-zero.cpp) [Python](.\u002FPython\u002Fmake-array-elements-equal-to-zero.py) | _O(n)_   | _O(n)_        | Easy         | [CodeChef Starters 146 - Bouncing Ball](https:\u002F\u002Fwww.codechef.com\u002Fproblems\u002FBOUNCE_BALL) | Prefix Sum\n3355 | [Zero Array Transformation I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fzero-array-transformation-i\u002F) | [C++](.\u002FC++\u002Fzero-array-transformation-i.cpp) [Python](.\u002FPython\u002Fzero-array-transformation-i.py) | _O(n + q)_   | _O(n)_        | Medium         | | Line Sweep\n3361 | [Shift Distance Between Two Strings](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fshift-distance-between-two-strings\u002F) | [C++](.\u002FC++\u002Fshift-distance-between-two-strings.cpp) [Python](.\u002FPython\u002Fshift-distance-between-two-strings.py) | _O(n + 26)_   | _O(26)_        | Medium         | | Prefix Sum\n3379 | [Transformed Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ftransformed-array\u002F) | [C++](.\u002FC++\u002Ftransformed-array.cpp) [Python](.\u002FPython\u002Ftransformed-array.py) | _O(n)_   | _O(1)_        | Easy         | | Array\n3380 | [Maximum Area Rectangle With Point Constraints I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-area-rectangle-with-point-constraints-i\u002F) | [C++](.\u002FC++\u002Fmaximum-area-rectangle-with-point-constraints-i.cpp) [Python](.\u002FPython\u002Fmaximum-area-rectangle-with-point-constraints-i.py) | _O(nlogn)_   | _O(n)_        | Medium         | | Sort, Brute Force, BIT, Fenwick Tree, Hash Table\n3382 | [Maximum Area Rectangle With Point Constraints II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-area-rectangle-with-point-constraints-ii\u002F) | [C++](.\u002FC++\u002Fmaximum-area-rectangle-with-point-constraints-ii.cpp) [Python](.\u002FPython\u002Fmaximum-area-rectangle-with-point-constraints-ii.py) | _O(nlogn)_   | _O(n)_        | Hard         | | Sort, BIT, Fenwick Tree, Hash Table\n3386 | [Button with Longest Push Time](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fbutton-with-longest-push-time\u002F) | [C++](.\u002FC++\u002Fbutton-with-longest-push-time.cpp) [Python](.\u002FPython\u002Fbutton-with-longest-push-time.py) | _O(n)_   | _O(1)_        | Easy         | | Array\n3392 | [Count Subarrays of Length Three With a Condition](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-subarrays-of-length-three-with-a-condition\u002F) | [C++](.\u002FC++\u002Fcount-subarrays-of-length-three-with-a-condition.cpp) [Python](.\u002FPython\u002Fcount-subarrays-of-length-three-with-a-condition.py) | _O(n)_   | _O(1)_        | Easy         | | Array\n3400 | [Maximum Number of Matching Indices After Right Shifts](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-number-of-matching-indices-after-right-shifts\u002F) | [C++](.\u002FC++\u002Fmaximum-number-of-matching-indices-after-right-shifts.cpp) [Python](.\u002FPython\u002Fmaximum-number-of-matching-indices-after-right-shifts.py) | _O(n^2)_ | _O(1)_ | Medium | 🔒 | Brute Force\n3417 | [Zigzag Grid Traversal With Skip](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fzigzag-grid-traversal-with-skip\u002F) | [C++](.\u002FC++\u002Fzigzag-grid-traversal-with-skip.cpp) [Python](.\u002FPython\u002Fzigzag-grid-traversal-with-skip.py) | _O(n * m)_ | _O(1)_ | Easy | | Array\n3423 | [Maximum Difference Between Adjacent Elements in a Circular Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fzmaximum-difference-between-adjacent-elements-in-a-circular-array\u002F) | [C++](.\u002FC++\u002Fmaximum-difference-between-adjacent-elements-in-a-circular-array.cpp) [Python](.\u002FPython\u002Fmaximum-difference-between-adjacent-elements-in-a-circular-array.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3427 | [Sum of Variable Length Subarrays](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsum-of-variable-length-subarrays\u002F) | [C++](.\u002FC++\u002Fsum-of-variable-length-subarrays.cpp) [Python](.\u002FPython\u002Fsum-of-variable-length-subarrays.py) | _O(n)_   | _O(n)_        | Easy         | | Difference Array\n3432 | [Count Partitions with Even Sum Difference](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-partitions-with-even-sum-difference\u002F) | [C++](.\u002FC++\u002Fcount-partitions-with-even-sum-difference.cpp) [Python](.\u002FPython\u002Fcount-partitions-with-even-sum-difference.py) | _O(n)_   | _O(1)_        | Easy         | | Prefix Sum\n3440 | [Reschedule Meetings for Maximum Free Time II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Freschedule-meetings-for-maximum-free-time-ii\u002F) | [C++](.\u002FC++\u002Freschedule-meetings-for-maximum-free-time-ii.cpp) [Python](.\u002FPython\u002Freschedule-meetings-for-maximum-free-time-ii.py) | _O(n)_ | _O(1)_ | Medium | | Array\n3446 | [Sort Matrix by Diagonals](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsort-matrix-by-diagonals\u002F) | [C++](.\u002FC++\u002Fsort-matrix-by-diagonals.cpp) [Python](.\u002FPython\u002Fsort-matrix-by-diagonals.py) | _O(n^2 * logn)_ | _O(n^2)_ | Medium | | Array, Sort\n3452 | [Sum of Good Numbers](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsum-of-good-numbers\u002F) | [C++](.\u002FC++\u002Fsum-of-good-numbers.cpp) [Python](.\u002FPython\u002Fsum-of-good-numbers.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3467 | [Transform Array by Parity](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ftransform-array-by-parity\u002F) | [C++](.\u002FC++\u002Ftransform-array-by-parity.cpp) [Python](.\u002FPython\u002Ftransform-array-by-parity.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3502 | [Minimum Cost to Reach Every Position](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-cost-to-reach-every-position\u002F) | [C++](.\u002FC++\u002Fminimum-cost-to-reach-every-position.cpp) [Python](.\u002FPython\u002Fminimum-cost-to-reach-every-position.py) | _O(n)_ | _O(1)_ | Easy | | Prefix Sum\n3514 | [Number of Unique XOR Triplets II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-unique-xor-triplets-ii\u002F) | [C++](.\u002FC++\u002Fnumber-of-unique-xor-triplets-ii.cpp) [Python](.\u002FPython\u002Fnumber-of-unique-xor-triplets-ii.py) | _O(nlogn)_ | _O(n)_ | Medium | | `Fast Walsh–Hadamard Transform`, FWHT, `Fast Subset Transform`, FST, Hash Table\n3531 | [Count Covered Buildings](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-covered-buildings\u002F) | [C++](.\u002FC++\u002Fcount-covered-buildings.cpp) [Python](.\u002FPython\u002Fcount-covered-buildings.py) | _O(n)_ | _O(n)_ | Medium | | Array\n3537 | [Fill a Special Grid](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffill-a-special-grid\u002F) | [C++](.\u002FC++\u002Ffill-a-special-grid.cpp) [Python](.\u002FPython\u002Ffill-a-special-grid.py) | _O(4^n)_ | _O(1)_ | Medium | | Divide and Conquer, Array\n3540 | [Minimum Time to Visit All Houses](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-time-to-visit-all-houses\u002F) | [C++](.\u002FC++\u002Fminimum-time-to-visit-all-houses.cpp) [Python](.\u002FPython\u002Fminimum-time-to-visit-all-houses.py) | _O(n + q)_ | _O(n)_ | Medium | 🔒 | Prefix Sum\n3546 | [Equal Sum Grid Partition I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fequal-sum-grid-partition-i\u002F) | [C++](.\u002FC++\u002Fequal-sum-grid-partition-i.cpp) [Python](.\u002FPython\u002Fequal-sum-grid-partition-i.py) | _O(m * n)_ | _O(1)_ | Medium | | Array\n3548 | [Equal Sum Grid Partition II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fequal-sum-grid-partition-ii\u002F) | [C++](.\u002FC++\u002Fequal-sum-grid-partition-ii.cpp) [Python](.\u002FPython\u002Fequal-sum-grid-partition-ii.py) | _O(m * n)_ | _O(m * n)_ | Hard | | Array, Hash Table\n3549 | [Multiply Two Polynomials](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmultiply-two-polynomials\u002F) | [C++](.\u002FC++\u002Fmultiply-two-polynomials.cpp) [Python](.\u002FPython\u002Fmultiply-two-polynomials.py) | _O((n + m) * log(n + m))_ | _O(n + m)_ | Hard | 🔒 | `Fast Fourier Transform`, FFT\n3550 | [Smallest Index With Digit Sum Equal to Index](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsmallest-index-with-digit-sum-equal-to-index\u002F) | [C++](.\u002FC++\u002Fsmallest-index-with-digit-sum-equal-to-index.cpp) [Python](.\u002FPython\u002Fsmallest-index-with-digit-sum-equal-to-index.py) | _O(nlogr)_ | _O(1)_ | Easy | | Array\n3569 | [Maximize Count of Distinct Primes After Split](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximize-count-of-distinct-primes-after-splitx\u002F) | [C++](.\u002FC++\u002Fmaximize-count-of-distinct-primes-after-split.cpp) [Python](.\u002FPython\u002Fmaximize-count-of-distinct-primes-after-split.py) | _O(r + nlogn + qlogn)_ | _O(r + n)_ | Medium | | Number Theory, BST, Sorted List, Segment Tree\n3637 | [Trionic Array I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ftrionic-array-i\u002F) | [C++](.\u002FC++\u002Ftrionic-array-i.cpp) [Python](.\u002FPython\u002Ftrionic-array-i.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3643 | [Flip Square Submatrix Vertically](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fflip-square-submatrix-vertically\u002F) | [C++](.\u002FC++\u002Fflip-square-submatrix-vertically.cpp) [Python](.\u002FPython\u002Fflip-square-submatrix-vertically.py) | _O(k^2)_ | _O(1)_ | Easy | | Array\n3653 | [XOR After Range Multiplication Queries I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fxor-after-range-multiplication-queries-i\u002F) | [C++](.\u002FC++\u002Fxor-after-range-multiplication-queries-i.cpp) [Python](.\u002FPython\u002Fxor-after-range-multiplication-queries-i.py) | _O(qlogm + (q + n) * sqrt(n))_ | _O(n * sqrt(n))_ | Medium || Sqrt Decomposition, Difference Array, Fast Exponentiation, Simulation\n3655 | [XOR After Range Multiplication Queries II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fxor-after-range-multiplication-queries-ii\u002F) | [C++](.\u002FC++\u002Fxor-after-range-multiplication-queries-ii.cpp) [Python](.\u002FPython\u002Fxor-after-range-multiplication-queries-ii.py) | _O(qlogm + (q + n) * sqrt(n))_ | _O(n * sqrt(n))_ | Hard || Sqrt Decomposition, Difference Array, Fast Exponentiation\n3674 | [Minimum Operations to Equalize Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-operations-to-equalize-array\u002F) | [C++](.\u002FC++\u002Fminimum-operations-to-equalize-array.cpp) [Python](.\u002FPython\u002Fminimum-operations-to-equalize-array.py) | _O(n)_ | _O(1)_ | Easy || Array\n3683 | [Earliest Time to Finish One Task](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fearliest-time-to-finish-one-task\u002F) | [C++](.\u002FC++\u002Fearliest-time-to-finish-one-task.cpp) [Python](.\u002FPython\u002Fearliest-time-to-finish-one-task.py) | _O(n)_ | _O(1)_ | Easy || Array\n3687 | [Library Late Fee Calculator](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flibrary-late-fee-calculator\u002F) | [C++](.\u002FC++\u002Flibrary-late-fee-calculator.cpp) [Python](.\u002FPython\u002Flibrary-late-fee-calculator.py) | _O(n)_ | _O(1)_ | Easy |🔒| Array\n3688 | [Bitwise OR of Even Numbers in an Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fbitwise-or-of-even-numbers-in-an-array\u002F) | [C++](.\u002FC++\u002Fbitwise-or-of-even-numbers-in-an-array.cpp) [Python](.\u002FPython\u002Fbitwise-or-of-even-numbers-in-an-array.py) | _O(n)_ | _O(1)_ | Easy || Array\n3696 | [Maximum Distance Between Unequal Words in Array I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-distance-between-unequal-words-in-array-i\u002F) | [C++](.\u002FC++\u002Fmaximum-distance-between-unequal-words-in-array-i.cpp) [Python](.\u002FPython\u002Fmaximum-distance-between-unequal-words-in-array-i.py) | _O(n * l)_ | _O(1)_ | Easy |🔒| Array\n3700 | [Number of ZigZag Arrays II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-zigzag-arrays-ii\u002F) | [C++](.\u002FC++\u002Fnumber-of-zigzag-arrays-ii.cpp) [Python](.\u002FPython\u002Fnumber-of-zigzag-arrays-ii.py) | _O((r - l)^3 * logn)_   | _O((r - l)^2)_        | Hard         | | Matrix Exponentiation\n3701 | [Compute Alternating Sum](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcompute-alternating-sum\u002F) | [C++](.\u002FC++\u002Fcompute-alternating-sum.cpp) [Python](.\u002FPython\u002Fcompute-alternating-sum.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3706 | [Maximum Distance Between Unequal Words in Array II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-distance-between-unequal-words-in-array-ii\u002F) | [C++](.\u002FC++\u002Fmaximum-distance-between-unequal-words-in-array-ii.cpp) [Python](.\u002FPython\u002Fmaximum-distance-between-unequal-words-in-array-ii.py) | _O(n * l)_ | _O(1)_ | Medium |🔒| Array\n3707 | [Equal Score Substrings](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fequal-score-substrings\u002F) | [C++](.\u002FC++\u002Fequal-score-substrings.cpp) [Python](.\u002FPython\u002Fequal-score-substrings.py) | _O(n)_ | _O(1)_ | Easy | | Array, Prefix Sum\n3708 | [Longest Fibonacci Subarray](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-fibonacci-subarray\u002F) | [C++](.\u002FC++\u002Flongest-fibonacci-subarray.cpp) [Python](.\u002FPython\u002Flongest-fibonacci-subarray.py) | _O(n)_ | _O(1)_ | Medium | | Array\n3719 | [Longest Balanced Subarray I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-balanced-subarray-i\u002F) | [C++](.\u002FC++\u002Flongest-balanced-subarray-i.cpp) [Python](.\u002FPython\u002Flongest-balanced-subarray-i.py) | _O(nlogn)_ | _O(n)_ | Medium | | Brute Force, Segment Tree, Binary Search, Prefix Sum\n3721 | [Longest Balanced Subarray II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-balanced-subarray-ii\u002F) | [C++](.\u002FC++\u002Flongest-balanced-subarray-ii.cpp) [Python](.\u002FPython\u002Flongest-balanced-subarray-ii.py) | _O(nlogn)_ | _O(n)_ | Hard | | Segment Tree, Binary Search, Prefix Sum\n3736 | [Minimum Moves to Equal Array Elements III](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-moves-to-equal-array-elements-iii\u002F) | [C++](.\u002FC++\u002Fminimum-moves-to-equal-array-elements-iii.cpp) [Python](.\u002FPython\u002Fminimum-moves-to-equal-array-elements-iii.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3737 | [Count Subarrays With Majority Element I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-subarrays-with-majority-element-i\u002F) | [C++](.\u002FC++\u002Fcount-subarrays-with-majority-element-i.cpp) [Python](.\u002FPython\u002Fcount-subarrays-with-majority-element-i.py) | _O(n)_ | _O(n)_ | Medium | | Freq Table, Prefix Sum\n3738 | [Longest Non-Decreasing Subarray After Replacing at Most One Element](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-non-decreasing-subarray-after-replacing-at-most-one-element\u002F) | [C++](.\u002FC++\u002Flongest-non-decreasing-subarray-after-replacing-at-most-one-element.cpp) [Python](.\u002FPython\u002Flongest-non-decreasing-subarray-after-replacing-at-most-one-element.py) | _O(n)_ | _O(n)_ | Medium | | Array, Prefix Sum\n3739 | [Count Subarrays With Majority Element II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-subarrays-with-majority-element-ii\u002F) | [C++](.\u002FC++\u002Fcount-subarrays-with-majority-element-ii.cpp) [Python](.\u002FPython\u002Fcount-subarrays-with-majority-element-ii.py) | _O(n)_ | _O(n)_ | Hard | | Freq Table, Prefix Sum\n3751 | [Total Waviness of Numbers in Range I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ftotal-waviness-of-numbers-in-range-i\u002F) | [C++](.\u002FC++\u002Ftotal-waviness-of-numbers-in-range-i.cpp) [Python](.\u002FPython\u002Ftotal-waviness-of-numbers-in-range-i.py) | _O(nlogn)_ | _O(logn)_ | Medium | | Brute Force\n3756 | [Concatenate Non-Zero Digits and Multiply by Sum II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconcatenate-non-zero-digits-and-multiply-by-sum-ii\u002F) | [C++](.\u002FC++\u002Fconcatenate-non-zero-digits-and-multiply-by-sum-ii.cpp) [Python](.\u002FPython\u002Fconcatenate-non-zero-digits-and-multiply-by-sum-ii.py) | _O(n)_ | _O(n)_ | Medium | | Prefix Sum |\n3762 | [Minimum Operations to Equalize Subarrays](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-operations-to-equalize-subarrays\u002F) | [C++](.\u002FC++\u002Fminimum-operations-to-equalize-subarrays.cpp) [Python](.\u002FPython\u002Fminimum-operations-to-equalize-subarrays.py) | _O((n + q) * logn)_ | _O(nlogn)_ | Hard | | Prefix Sum, Coordinate Compression, Persistent Segment Tree, Binary Search |\n3774 | [Absolute Difference Between Maximum and Minimum K Elements](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fabsolute-difference-between-maximum-and-minimum-k-elements\u002F) | [C++](.\u002FC++\u002Fabsolute-difference-between-maximum-and-minimum-k-elements.cpp) [Python](.\u002FPython\u002Fabsolute-difference-between-maximum-and-minimum-k-elements.py) | _O(n)_ | _O(1)_ | Easy | | Sort, Quick Select\n3788 | [Maximum Score of a Split](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-score-of-a-split\u002F) | [C++](.\u002FC++\u002Fmaximum-score-of-a-split.cpp) [Python](.\u002FPython\u002Fmaximum-score-of-a-split.py) | _O(n)_ | _O(1)_ | Medium | | Prefix Sum\n3809 | [Best Reachable Tower](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fbest-reachable-tower\u002F) | [C++](.\u002FC++\u002Fbest-reachable-tower.cpp) [Python](.\u002FPython\u002Fbest-reachable-tower.py) | _O(n)_ | _O(1)_ | Medium | | Array\n3814 | [Maximum Capacity Within Budget](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-capacity-within-budget\u002F) | [C++](.\u002FC++\u002Fmaximum-capacity-within-budget.cpp) [Python](.\u002FPython\u002Fmaximum-capacity-within-budget.py) | _O(n + b)_ | _O(b)_ | Medium | | Hash Table, Prefix Sum, Sort, Mono Stack, Binary Search\n3818 | [Minimum Prefix Removal to Make Array Strictly Increasing](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-prefix-removal-to-make-array-strictly-increasing\u002F) | [C++](.\u002FC++\u002Fminimum-prefix-removal-to-make-array-strictly-increasing.cpp) [Python](.\u002FPython\u002Fminimum-prefix-removal-to-make-array-strictly-increasing.py) | _O(n)_ | _O(1)_ | Medium | | Array\n3819 | [Rotate Non Negative Elements](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Frotate-non-negative-elements\u002F) | [C++](.\u002FC++\u002Frotate-non-negative-elements.cpp) [Python](.\u002FPython\u002Frotate-non-negative-elements.py) | _O(n)_ | _O(n)_ | Medium | | Array\n3833 | [Count Dominant Indices](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-dominant-indices\u002F) | [C++](.\u002FC++\u002Fcount-dominant-indices.cpp) [Python](.\u002FPython\u002Fcount-dominant-indices.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3861 | [Minimum Capacity Box](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-capacity-box\u002F) | [C++](.\u002FC++\u002Fminimum-capacity-box.cpp) [Python](.\u002FPython\u002Fminimum-capacity-box.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3862 | [Find the Smallest Balanced Index](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-smallest-balanced-index\u002F) | [C++](.\u002FC++\u002Ffind-the-smallest-balanced-index.cpp) [Python](.\u002FPython\u002Ffind-the-smallest-balanced-index.py) | _O(n)_ | _O(1)_ | Medium | | Prefix Sum\n3865 | [Reverse K Subarrays](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Freverse-k-subarrays\u002F) | [C++](.\u002FC++\u002Freverse-k-subarrays.cpp) [Python](.\u002FPython\u002Freverse-k-subarrays.py) | _O(n)_ | _O(1)_ | Medium | 🔒 | Array\n3880 | [Minimum Absolute Difference Between Two Values](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-absolute-difference-between-two-values\u002F) | [C++](.\u002FC++\u002Fminimum-absolute-difference-between-two-values.cpp) [Python](.\u002FPython\u002Fminimum-absolute-difference-between-two-values.py) | _O(n)_ | _O(1)_ | Easy | | Array\n3898 | [Find the Degree of Each Vertex](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-degree-of-each-vertex\u002F) | [C++](.\u002FC++\u002Ffind-the-degree-of-each-vertex.cpp) [Python](.\u002FPython\u002Ffind-the-degree-of-each-vertex.py) | _O(n * m)_ | _O(1)_ | Easy | | Array\n3903 | [Smallest Stable Index I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsmallest-stable-index-i\u002F) | [C++](.\u002FC++\u002Fsmallest-stable-index-i.cpp) [Python](.\u002FPython\u002Fsmallest-stable-index-i.py) | _O(n)_ | _O(n)_ | Easy | | Prefix Sum\n3904 | [Smallest Stable Index II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsmallest-stable-index-ii\u002F) | [C++](.\u002FC++\u002Fsmallest-stable-index-ii.cpp) [Python](.\u002FPython\u002Fsmallest-stable-index-ii.py) | _O(n)_ | _O(n)_ | Medium | | Prefix Sum\n3907 | [Count Smaller Elements With Opposite Parity](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-smaller-elements-with-opposite-parity\u002F) | [C++](.\u002FC++\u002Fcount-smaller-elements-with-opposite-parity.cpp) [Python](.\u002FPython\u002Fcount-smaller-elements-with-opposite-parity.py) | _O(nlogn)_ | _O(n)_ | Medium | 🔒 | Sort, Coordinate Compression, BIT, Fenwick Tree\n3909 | [Compare Sums of Bitonic Parts](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcompare-sums-of-bitonic-parts\u002F) | [C++](.\u002FC++\u002Fcompare-sums-of-bitonic-parts.cpp) [Python](.\u002FPython\u002Fcompare-sums-of-bitonic-parts.py) | _O(n)_ | _O(1)_ | Medium | | Array\n3912 | [Valid Elements in an Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fvalid-elements-in-an-array\u002F) | [C++](.\u002FC++\u002Fvalid-elements-in-an-array.cpp) [Python](.\u002FPython\u002Fvalid-elements-in-an-array.py) | _O(n)_ | _O(n)_ | Medium | | Prefix Sum\n3915 | [Maximum Sum of Alternating Subsequence With Distance at Least K](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-operations-to-make-array-non-decreasing\u002F) | [C++](.\u002FC++\u002Fminimum-operations-to-make-array-non-decreasing.cpp) [Python](.\u002FPython\u002Fminimum-operations-to-make-array-non-decreasing.py) | _O(nlogn)_ | _O(n)_ | Hard | | Sort, Coordinate Compression, BIT, Fenwick Tree, Sliding Window, DP\n3918 | [Sum of Primes Between Number and Its Reverse](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsum-of-primes-between-number-and-its-reverse\u002F) | [C++](.\u002FC++\u002Fsum-of-primes-between-number-and-its-reverse.cpp) [Python](.\u002FPython\u002Fsum-of-primes-between-number-and-its-reverse.py) | precompute: _O(r)_\u003Cbr>runtime: _O(1)_ | _O(r)_ | Medium | | Number Theory, `Linear Sieve of Eratosthenes`, Prefix Sum\n3925 | [Concatenate Array With Reverse](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconcatenate-array-with-reverse\u002F) | [C++](.\u002FC++\u002Fconcatenate-array-with-reverse.cpp) [Python](.\u002FPython\u002Fconcatenate-array-with-reverse.py) | _O(n)_ | _O(1)_ | Easy | | Array\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## String\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3019 | [Number of Changing Keys](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-changing-keys\u002F)| [C++](.\u002FC++\u002Fnumber-of-changing-keys.cpp) [Python](.\u002FPython\u002Fnumber-of-changing-keys.py)| _O(n)_ | _O(1)_ | Easy | | String |\n3023 | [Find Pattern in Infinite Stream I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-pattern-in-infinite-stream-i\u002F)| [C++](.\u002FC++\u002Ffind-pattern-in-infinite-stream-i.cpp) [Python](.\u002FPython\u002Ffind-pattern-in-infinite-stream-i.py)| _O(p + n)_ | _O(p)_ | Medium | 🔒 | String, `KMP Algorithm` |\n3029 | [Minimum Time to Revert Word to Initial State I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-time-to-revert-word-to-initial-state-i\u002F)| [C++](.\u002FC++\u002Fminimum-time-to-revert-word-to-initial-state-i.cpp) [Python](.\u002FPython\u002Fminimum-time-to-revert-word-to-initial-state-i.py)| _O(n)_ | _O(n)_ | Medium | | String, `Z-Function`, Brute Force |\n3031 | [Minimum Time to Revert Word to Initial State II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-time-to-revert-word-to-initial-state-ii\u002F)| [C++](.\u002FC++\u002Fminimum-time-to-revert-word-to-initial-state-ii.cpp) [Python](.\u002FPython\u002Fminimum-time-to-revert-word-to-initial-state-ii.py)| _O(n)_ | _O(n)_ | Hard | | String, `Z-Function` |\n3034 | [Number of Subarrays That Match a Pattern I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-subarrays-that-match-a-pattern-i\u002F)| [C++](.\u002FC++\u002Fnumber-of-subarrays-that-match-a-pattern-i.cpp) [Python](.\u002FPython\u002Fnumber-of-subarrays-that-match-a-pattern-i.py)| _O(n)_ | _O(m)_ | Medium | | Brute Force, String, `KMP Algorithm` |\n3036 | [Number of Subarrays That Match a Pattern II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-subarrays-that-match-a-pattern-ii\u002F)| [C++](.\u002FC++\u002Fnumber-of-subarrays-that-match-a-pattern-ii.cpp) [Python](.\u002FPython\u002Fnumber-of-subarrays-that-match-a-pattern-ii.py)| _O(n)_ | _O(m)_ | Hard | | String, `KMP Algorithm` |\n3037 | [Find Pattern in Infinite Stream II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-pattern-in-infinite-stream-ii\u002F)| [C++](.\u002FC++\u002Ffind-pattern-in-infinite-stream-ii.cpp) [Python](.\u002FPython\u002Ffind-pattern-in-infinite-stream-ii.py)| _O(p + n)_ | _O(p)_ | Hard | 🔒 | String, `KMP Algorithm` |\n3042 | [Count Prefix and Suffix Pairs I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-prefix-and-suffix-pairs-i\u002F)| [C++](.\u002FC++\u002Fcount-prefix-and-suffix-pairs-i.cpp) [Python](.\u002FPython\u002Fcount-prefix-and-suffix-pairs-i.py)| _O(n * l)_ | _O(t)_ | Easy | | Trie, Brute Force |\n3043 | [Find the Length of the Longest Common Prefix](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-length-of-the-longest-common-prefix\u002F)| [C++](.\u002FC++\u002Ffind-the-length-of-the-longest-common-prefix.cpp) [Python](.\u002FPython\u002Ffind-the-length-of-the-longest-common-prefix.py)| _O((n + m) * l)_ | _O(t)_ | Medium | | Trie, Hash Table |\n3045 | [Count Prefix and Suffix Pairs II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-prefix-and-suffix-pairs-ii\u002F)| [C++](.\u002FC++\u002Fcount-prefix-and-suffix-pairs-ii.cpp) [Python](.\u002FPython\u002Fcount-prefix-and-suffix-pairs-ii.py)| _O(n * l)_ | _O(t)_ | Hard | | Trie |\n3076 | [Shortest Uncommon Substring in an Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fshortest-uncommon-substring-in-an-array\u002F)| [C++](.\u002FC++\u002Fshortest-uncommon-substring-in-an-array.cpp) [Python](.\u002FPython\u002Fshortest-uncommon-substring-in-an-array.py)| _O(n * l^2)_ | _O(t)_ | Medium | | Trie |\n3093 | [Longest Common Suffix Queries](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-common-suffix-queries\u002F)| [C++](.\u002FC++\u002Flongest-common-suffix-queries.cpp) [Python](.\u002FPython\u002Flongest-common-suffix-queries.py)| _O((n + q) * l)_ | _O(t)_ | Hard | | Trie |\n3110 | [Score of a String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fscore-of-a-string\u002F)| [C++](.\u002FC++\u002Fscore-of-a-string.cpp) [Python](.\u002FPython\u002Fscore-of-a-string.py)| _O(n)_ | _O(1)_ | Easy | | String |\n3136 | [Valid Word](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fvalid-word\u002F) | [C++](.\u002FC++\u002Fvalid-word.cpp) [Python](.\u002FPython\u002Fvalid-word.py) | _O(n)_ | _O(1)_ | Easy | | String\n3163 | [String Compression III](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fstring-compression-iii\u002F) | [C++](.\u002FC++\u002Fstring-compression-iii.cpp) [Python](.\u002FPython\u002Fstring-compression-iii.py) | _O(n)_ | _O(1)_ | Medium | | String\n3210 | [Find the Encrypted String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-encrypted-string\u002F) | [C++](.\u002FC++\u002Ffind-the-encrypted-string.cpp) [Python](.\u002FPython\u002Ffind-the-encrypted-string.py) | _O(n)_ | _O(1)_ | Medium | | String\n3271 | [Hash Divided String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fhash-divided-string\u002F) | [C++](.\u002FC++\u002Fhash-divided-string.cpp) [Python](.\u002FPython\u002Fhash-divided-string.py) | _O(n)_ | _O(1)_ | Medium | | String\n3280 | [Convert Date to Binary](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconvert-date-to-binary\u002F) | [C++](.\u002FC++\u002Fconvert-date-to-binary.cpp) [Python](.\u002FPython\u002Fconvert-date-to-binary.py) | _O(1)_ | _O(1)_ | Easy | | String\n3303 | [Find the Occurrence of First Almost Equal Substring](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-occurrence-of-first-almost-equal-substring\u002F) | [C++](.\u002FC++\u002Ffind-the-occurrence-of-first-almost-equal-substring.cpp) [Python](.\u002FPython\u002Ffind-the-occurrence-of-first-almost-equal-substring.py) | _O(n + m)_   | _O(n + m)_        | Hard         | | `Z-Function`\n3324 | [Find the Sequence of Strings Appeared on the Screen](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-sequence-of-strings-appeared-on-the-screen\u002F) | [C++](.\u002FC++\u002Ffind-the-sequence-of-strings-appeared-on-the-screen.cpp) [Python](.\u002FPython\u002Ffind-the-sequence-of-strings-appeared-on-the-screen.py) | _O(n^2)_   | _O(1)_        | Medium         | | String\n3340 | [Check Balanced String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcheck-balanced-string\u002F) | [C++](.\u002FC++\u002Fcheck-balanced-string.cpp) [Python](.\u002FPython\u002Fcheck-balanced-string.py) | _O(n)_   | _O(1)_        | Easy         | | String\n3407 | [Substring Matching Pattern](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsubstring-matching-pattern\u002F) | [C++](.\u002FC++\u002Fsubstring-matching-pattern.cpp) [Python](.\u002FPython\u002Fsubstring-matching-pattern.py) | _O(n + m)_   | _O(m)_        | Easy         | | String, `KMP Algorithm`\n3455 | [Shortest Matching Substring](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fshortest-matching-substring\u002F) | [C++](.\u002FC++\u002Fshortest-matching-substring.cpp) [Python](.\u002FPython\u002Fshortest-matching-substring.py) | _O(n + m)_   | _O(n + m)_        | Hard         | | String, `KMP Algorithm`, Two Pointers\n3456 | [Find Special Substring of Length K](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-special-substring-of-length-k\u002F) | [C++](.\u002FC++\u002Ffind-special-substring-of-length-k.cpp) [Python](.\u002FPython\u002Ffind-special-substring-of-length-k.py) | _O(n)_   | _O(1)_        | Easy         | | String\n3491 | [Phone Number Prefix](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fphone-number-prefix\u002F) | [C++](.\u002FC++\u002Fphone-number-prefix.cpp) [Python](.\u002FPython\u002Fphone-number-prefix.py) | _O(l * nlogn)_   | _O(1)_        | Easy         | 🔒 | Trie, Sort\n3498 | [Reverse Degree of a String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Freverse-degree-of-a-string\u002F) | [C++](.\u002FC++\u002Freverse-degree-of-a-string.cpp) [Python](.\u002FPython\u002Freverse-degree-of-a-string.py) | _O(n)_   | _O(1)_        | Easy         | | String\n3529 | [Count Cells in Overlapping Horizontal and Vertical Substrings](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-cells-in-overlapping-horizontal-and-vertical-substrings\u002F) | [C++](.\u002FC++\u002Fcount-cells-in-overlapping-horizontal-and-vertical-substrings.cpp) [Python](.\u002FPython\u002Fcount-cells-in-overlapping-horizontal-and-vertical-substrings.py) | _O(n * m)_ | _O(n * m)_ | Medium | | `Z-Function`\n3571 | [Find the Shortest Superstring II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-shortest-superstring-ii\u002F) | [C++](.\u002FC++\u002Ffind-the-shortest-superstring-ii.cpp) [Python](.\u002FPython\u002Ffind-the-shortest-superstring-ii.py) | _O(n + m)_ | _O(n + m)_ | Easy | 🔒 | `KMP Algorithm`\n3582 | [Generate Tag for Video Caption](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fgenerate-tag-for-video-caption\u002F) | [C++](.\u002FC++\u002Fgenerate-tag-for-video-caption.cpp) [Python](.\u002FPython\u002Fgenerate-tag-for-video-caption.py) | _O(n)_ | _O(1)_ | Easy | | String\n3598 | [Longest Common Prefix Between Adjacent Strings After Removals](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flongest-common-prefix-between-adjacent-strings-after-removals\u002F) | [C++](.\u002FC++\u002Flongest-common-prefix-between-adjacent-strings-after-removals.cpp) [Python](.\u002FPython\u002Flongest-common-prefix-between-adjacent-strings-after-removals.py) | _O(n * l)_ | _O(n)_ | Medium | | LCP, Prefix Sum\n3606 | [Coupon Code Validator](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcoupon-code-validator\u002F) | [C++](.\u002FC++\u002Fcoupon-code-validator.cpp) [Python](.\u002FPython\u002Fcoupon-code-validator.py) | _O(l * nlogn)_ | _O(n * l)_ | Easy | | Hash Table, Sort\n3744 | [Find Kth Character in Expanded String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-kth-character-in-expanded-string\u002F) | [C++](.\u002FC++\u002Ffind-kth-character-in-expanded-string.cpp) [Python](.\u002FPython\u002Ffind-kth-character-in-expanded-string.py) | _O(n)_ | _O(1)_ | Medium | 🔒 | String\n3746 | [Minimum String Length After Balanced Removals](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-string-length-after-balanced-removals\u002F) | [C++](.\u002FC++\u002Fminimum-string-length-after-balanced-removals.cpp) [Python](.\u002FPython\u002Fminimum-string-length-after-balanced-removals.py) | _O(n)_ | _O(1)_ | Medium | | String\n3748 | [Count Stable Subarrays](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-stable-subarrays\u002F) | [C++](.\u002FC++\u002Fcount-stable-subarrays.cpp) [Python](.\u002FPython\u002Fcount-stable-subarrays.py) | _O(n + q)_ | _O(n)_ | Hard | | Prefix Sum\n3758 | [Convert Number Words to Digits](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconvert-number-words-to-digits\u002F) | [C++](.\u002FC++\u002Fconvert-number-words-to-digits.cpp) [Python](.\u002FPython\u002Fconvert-number-words-to-digits.py) | _O(n)_ | _O(1)_ | Medium | 🔒 | String\n3775 | [Reverse Words With Same Vowel Count](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Freverse-words-with-same-vowel-count\u002F) | [C++](.\u002FC++\u002Freverse-words-with-same-vowel-count.cpp) [Python](.\u002FPython\u002Freverse-words-with-same-vowel-count.py) | _O(n)_ | _O(1)_ | Medium | | String, Inplace\n3777 | [Minimum Deletions to Make Alternating Substring](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-deletions-to-make-alternating-substring\u002F) | [C++](.\u002FC++\u002Fminimum-deletions-to-make-alternating-substring.cpp) [Python](.\u002FPython\u002Fminimum-deletions-to-make-alternating-substring.py) | _O((n + q) * logn)_ | _O(n)_ | Hard | | BIT, Fenwick Tree\n3794 | [Reverse String Prefix](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Freverse-string-prefix\u002F) | [C++](.\u002FC++\u002Freverse-string-prefix.cpp) [Python](.\u002FPython\u002Freverse-string-prefix.py) | _O(n)_ | _O(1)_ | Easy | | String\n3813 | [Vowel-Consonant Score](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fvowel-consonant-score\u002F) | [C++](.\u002FC++\u002Fvowel-consonant-score.cpp) [Python](.\u002FPython\u002Fvowel-consonant-score.py) | _O(n)_ | _O(1)_ | Easy | | String\n3823 | [Reverse Letters Then Special Characters in a String](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Freverse-letters-then-special-characters-in-a-string\u002F) | [C++](.\u002FC++\u002Freverse-letters-then-special-characters-in-a-string.cpp) [Python](.\u002FPython\u002Freverse-letters-then-special-characters-in-a-string.py) | _O(n)_ | _O(1)_ | Easy | | String\n3838 | [Weighted Word Mapping](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fweighted-word-mapping\u002F) | [C++](.\u002FC++\u002Fweighted-word-mapping.cpp) [Python](.\u002FPython\u002Fweighted-word-mapping.py) | _O(n * l)_ | _O(1)_ | Easy | | String\n3856 | [Trim Trailing Vowels](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ftrim-trailing-vowels\u002F) | [C++](.\u002FC++\u002Ftrim-trailing-vowels.cpp) [Python](.\u002FPython\u002Ftrim-trailing-vowels.py) | _O(n)_ | _O(1)_ | Easy | | String\n3860 | [Unique Email Groups](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Funique-email-groups\u002F) | [C++](.\u002FC++\u002Funique-email-groups.cpp) [Python](.\u002FPython\u002Funique-email-groups.py) | _O(n * l)_ | _O(n * l)_ | Medium | 🔒 | String, Hash Table\n3884 | [First Matching Character From Both Ends](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffirst-matching-character-from-both-ends\u002F) | [C++](.\u002FC++\u002Ffirst-matching-character-from-both-ends.cpp) [Python](.\u002FPython\u002Ffirst-matching-character-from-both-ends.py) | _O(n)_ | _O(1)_ | Medium | | String\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## Linked List\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3062 | [Winner of the Linked List Game](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fwinner-of-the-linked-list-game\u002F) | [C++](.\u002FC++\u002Fwinner-of-the-linked-list-game.cpp) [Python](.\u002FPython\u002Fwinner-of-the-linked-list-game.py) | _O(n)_ | _O(1)_ | Easy | 🔒 | Linked List\n3063 | [Linked List Frequency](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Flinked-list-frequency\u002F) | [C++](.\u002FC++\u002Flinked-list-frequency.cpp) [Python](.\u002FPython\u002Flinked-list-frequency.py) | _O(n)_ | _O(1)_ | Medium | 🔒 | Linked List\n3217 | [Delete Nodes From Linked List Present in Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fdelete-nodes-from-linked-list-present-in-array\u002F) | [C++](.\u002FC++\u002Fdelete-nodes-from-linked-list-present-in-array.cpp) [Python](.\u002FPython\u002Fdelete-nodes-from-linked-list-present-in-array.py) | _O(n)_ | _O(m)_ | Medium | | Hash Table, Linked List\n3263 | [Convert Doubly Linked List to Array I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconvert-doubly-linked-list-to-array-i\u002F) | [C++](.\u002FC++\u002Fconvert-doubly-linked-list-to-array-i.cpp) [Python](.\u002FPython\u002Fconvert-doubly-linked-list-to-array-i.py) | _O(n)_ | _O(1)_ | Easy | 🔒 | Linked List\n3294 | [Convert Doubly Linked List to Array II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fconvert-doubly-linked-list-to-array-ii\u002F) | [C++](.\u002FC++\u002Fconvert-doubly-linked-list-to-array-ii.cpp) [Python](.\u002FPython\u002Fconvert-doubly-linked-list-to-array-ii.py) | _O(n)_ | _O(1)_ | Medium | 🔒 | Linked List\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## Stack\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3113 | [Find the Number of Subarrays Where Boundary Elements Are Maximum](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-number-of-subarrays-where-boundary-elements-are-maximum\u002F) | [C++](.\u002FC++\u002Ffind-the-number-of-subarrays-where-boundary-elements-are-maximum.cpp) [Python](.\u002FPython\u002Ffind-the-number-of-subarrays-where-boundary-elements-are-maximum.py) | _O(n)_ | _O(n)_ | Hard | | Mono Stack, Combinatorics\n3174 | [Clear Digits](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fclear-digits\u002F) | [C++](.\u002FC++\u002Fclear-digits.cpp) [Python](.\u002FPython\u002Fclear-digits.py) | _O(n)_ | _O(1)_ | Easy | | Stack, Two Pointers\n3676 | [Count Bowl Subarrays](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-bowl-subarrays\u002F) | [C++](.\u002FC++\u002Fcount-bowl-subarrays.cpp) [Python](.\u002FPython\u002Fcount-bowl-subarrays.py) | _O(n)_ | _O(n)_ | Medium | | Mono Stack\n3703 | [Remove K-Balanced Substrings](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fremove-k-balanced-substrings\u002F) | [C++](.\u002FC++\u002Fremove-k-balanced-substrings.cpp) [Python](.\u002FPython\u002Fremove-k-balanced-substrings.py) | _O(n)_ | _O(n)_ | Medium | | Stack\n3749 | [Evaluate Valid Expressions](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fevaluate-valid-expressions\u002F) | [C++](.\u002FC++\u002Fevaluate-valid-expressions.cpp) [Python](.\u002FPython\u002Fevaluate-valid-expressions.py) | _O(n)_ | _O(n)_ | Hard | 🔒 | Stack\n3834 | [Merge Adjacent Equal Elements](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmerge-adjacent-equal-elements\u002F) | [C++](.\u002FC++\u002Fmerge-adjacent-equal-elements.cpp) [Python](.\u002FPython\u002Fmerge-adjacent-equal-elements.py) | _O(n)_ | _O(1)_ | Medium | | Stack, Simulation\n3878 | [Count Good Subarrays](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-good-subarrays\u002F) | [C++](.\u002FC++\u002Fcount-good-subarrays.cpp) [Python](.\u002FPython\u002Fcount-good-subarrays.py) | _O(n)_ | _O(n)_ | Hard | | Combinatorics, Mono Stack\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## Queue\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## Binary Heap\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3066 | [Minimum Operations to Exceed Threshold Value II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-operations-to-exceed-threshold-value-ii\u002F) | [C++](.\u002FC++\u002Fminimum-operations-to-exceed-threshold-value-ii.cpp) [Python](.\u002FPython\u002Fminimum-operations-to-exceed-threshold-value-ii.py) | _O(nlogn)_ | _O(n)_ | Medium | | Simulation, Heap\n3080 | [Mark Elements on Array by Performing Queries](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmark-elements-on-array-by-performing-queries\u002F) | [C++](.\u002FC++\u002Fmark-elements-on-array-by-performing-queries.cpp) [Python](.\u002FPython\u002Fmark-elements-on-array-by-performing-queries.py) | _O(q + nlogn)_ | _O(n)_ | Medium | | Hash Table, Heap\n3092 | [Most Frequent IDs](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmost-frequent-ids\u002F) | [C++](.\u002FC++\u002Fmost-frequent-ids.cpp) [Python](.\u002FPython\u002Fmost-frequent-ids.py) | _O(nlogn)_ | _O(n)_ | Medium | | Heap, BST, Sorted List\n3256 | [Maximum Value Sum by Placing Three Rooks I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-value-sum-by-placing-three-rooks-i\u002F) | [C++](.\u002FC++\u002Fmaximum-value-sum-by-placing-three-rooks-i.cpp) [Python](.\u002FPython\u002Fmaximum-value-sum-by-placing-three-rooks-i.py) | _O(m * n)_ | _O(m + n)_ | Hard | | Heap, Brute Force\n3257 | [Maximum Value Sum by Placing Three Rooks II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-value-sum-by-placing-three-rooks-ii\u002F) | [C++](.\u002FC++\u002Fmaximum-value-sum-by-placing-three-rooks-ii.cpp) [Python](.\u002FPython\u002Fmaximum-value-sum-by-placing-three-rooks-ii.py) | _O(m * n)_ | _O(m + n)_ | Hard | | Heap, Brute Force\n3275 | [K-th Nearest Obstacle Queries](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fk-th-nearest-obstacle-queries\u002F) | [C++](.\u002FC++\u002Fk-th-nearest-obstacle-queries.cpp) [Python](.\u002FPython\u002Fk-th-nearest-obstacle-queries.py) | _O(qlogk)_ | _O(k)_ | Medium | | Heap\n3684 | [Maximize Sum of At Most K Distinct Elements](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximize-sum-of-at-most-k-distinct-elements\u002F) | [C++](.\u002FC++\u002Fmaximize-sum-of-at-most-k-distinct-elements.cpp) [Python](.\u002FPython\u002Fmaximize-sum-of-at-most-k-distinct-elements.py) | _O(nlogk)_ | _O(k)_ | Easy | | Heap, Sort\n3691 | [Maximum Total Subarray Value II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-total-subarray-value-ii\u002F) | [C++](.\u002FC++\u002Fmaximum-total-subarray-value-ii.cpp) [Python](.\u002FPython\u002Fmaximum-total-subarray-value-ii.py) | _O((n + k) * logn)_   | _O(n)_        | Hard         | | Heap, Sort, Two Pointers, RMQ, Sparse Table, Segment Tree\n3781 | [Maximum Score After Binary Swaps](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-score-after-binary-swaps\u002F) | [C++](.\u002FC++\u002Fmaximum-score-after-binary-swaps.cpp) [Python](.\u002FPython\u002Fmaximum-score-after-binary-swaps.py) | _O(nlogn)_   | _O(n)_        | Medium         | | Heap\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## Tree\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3109 | [Find the Index of Permutation](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-the-index-of-permutation\u002F)| [C++](.\u002FC++\u002Ffind-the-index-of-permutation.cpp) [Python](.\u002FPython\u002Ffind-the-index-of-permutation.py)| _O(nlogn)_ | _O(n)_ | 🔒, Medium | variant of [Count of Smaller Numbers After Self](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-of-smaller-numbers-after-self\u002F) | BIT, Fenwick Tree, Combinatorics |\n3515 | [Shortest Path in a Weighted Tree](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fshortest-path-in-a-weighted-tree\u002F)| [C++](.\u002FC++\u002Fshortest-path-in-a-weighted-tree.cpp) [Python](.\u002FPython\u002Fshortest-path-in-a-weighted-tree.py)| _O(nlogn)_ | _O(n)_ | Hard |  | BIT, Fenwick Tree, DFS |\n3553 | [Minimum Weighted Subgraph With the Required Paths II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fminimum-weighted-subgraph-with-the-required-paths-ii\u002F)| [C++](.\u002FC++\u002Fminimum-weighted-subgraph-with-the-required-paths-ii.cpp) [Python](.\u002FPython\u002Fminimum-weighted-subgraph-with-the-required-paths-ii.py)| _O(n + q)_ | _O(n + q)_ | Hard | | Tree, DFS, `Tarjan's Offline LCA Algorithm` |\n3558 | [Number of Ways to Assign Edge Weights I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-ways-to-assign-edge-weights-i\u002F)| [C++](.\u002FC++\u002Fnumber-of-ways-to-assign-edge-weights-i.cpp) [Python](.\u002FPython\u002Fnumber-of-ways-to-assign-edge-weights-i.py)| _O(n)_ | _O(n)_ | Medium | | Tree, BFS, Combinatorics |\n3559 | [Number of Ways to Assign Edge Weights II](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fnumber-of-ways-to-assign-edge-weights-ii\u002F)| [C++](.\u002FC++\u002Fnumber-of-ways-to-assign-edge-weights-ii.cpp) [Python](.\u002FPython\u002Fnumber-of-ways-to-assign-edge-weights-ii.py)| _O(n + q)_ | _O(n + q)_ | Medium | | Tree, DFS, `Tarjan's Offline LCA Algorithm`, Combinatorics |\n3585 | [Find Weighted Median Node in Tree](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Ffind-weighted-median-node-in-tree\u002F)| [C++](.\u002FC++\u002Ffind-weighted-median-node-in-tree.cpp) [Python](.\u002FPython\u002Ffind-weighted-median-node-in-tree.py)| _O(n + qlogh)_ | _O(n + q)_ | Hard | | Tree, DFS, `Tarjan's Offline LCA Algorithm`, Binary Search, Prefix Sum |\n3715 | [Sum of Perfect Square Ancestors](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsum-of-perfect-square-ancestors\u002F)| [C++](.\u002FC++\u002Fsum-of-perfect-square-ancestors.cpp) [Python](.\u002FPython\u002Fsum-of-perfect-square-ancestors.py)| precompute: _O(r)_\u003Cbr>runtime: _O(nlogx)_ | _O(r + n)_ | Hard | | Tree, Number Theory, `Linear Sieve of Eratosthenes`, Freq Table, DFS |\n3841 | [Palindromic Path Queries in a Tree](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fpalindromic-path-queries-in-a-tree\u002F)| [C++](.\u002FC++\u002Fpalindromic-path-queries-in-a-tree.cpp) [Python](.\u002FPython\u002Fpalindromic-path-queries-in-a-tree.py)| _O((n + q) * logn)_ | _O(n)_ | Hard | | DFS, HLD, Heavy-Light Decomposition, LCA, Binary Lifting, BIT, Fenwick Tree |\n3879 | [Maximum Distinct Path Sum in a Binary Tree](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmaximum-distinct-path-sum-in-a-binary-tree\u002F)| [C++](.\u002FC++\u002Fmaximum-distinct-path-sum-in-a-binary-tree.cpp) [Python](.\u002FPython\u002Fmaximum-distinct-path-sum-in-a-binary-tree.py)| _O(n^2)_ | _O(n)_ | Medium | | DFS, BFS\n\n\u003Cbr\u002F>\n\u003Cdiv align=\"right\">\n    \u003Cb>\u003Ca href=\"#algorithms\">⬆️ Back to Top\u003C\u002Fa>\u003C\u002Fb>\n\u003C\u002Fdiv>\n\u003Cbr\u002F>\n\n## Hash Table\n|  #  | Title           |  Solution       |  Time           | Space           | Difficulty    | Tag          | Note| \n|-----|---------------- | --------------- | --------------- | --------------- | ------------- |--------------|-----|\n3005 | [Count Elements With Maximum Frequency](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fcount-elements-with-maximum-frequency\u002F) | [C++](.\u002FC++\u002Fcount-elements-with-maximum-frequency.cpp) [Python](.\u002FPython\u002Fcount-elements-with-maximum-frequency.py) | _O(n)_ | _O(n)_ | Easy || Freq Table\n3039 | [Apply Operations to Make String Empty](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fapply-operations-to-make-string-empty\u002F) | [C++](.\u002FC++\u002Fapply-operations-to-make-string-empty.cpp) [Python](.\u002FPython\u002Fapply-operations-to-make-string-empty.py) | _O(n)_ | _O(1)_ | Medium || Freq Table\n3044 | [Most Frequent Prime](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmost-frequent-prime\u002F) | [C++](.\u002FC++\u002Fmost-frequent-prime.cpp) [Python](.\u002FPython\u002Fmost-frequent-prime.py) | precompute: _O(10^MAX_N_M)_\u003Cbr>runtime: _O(n * m * (n + m))_  | _O(10^MAX_N_M + n * m * (n + m))_ | Medium || Number Theory, `Linear Sieve of Eratosthenes`, Freq Table\n3046 | [Split the Array](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fsplit-the-array\u002F) | [C++](.\u002FC++\u002Fsplit-the-array.cpp) [Python](.\u002FPython\u002Fsplit-the-array.py) | _O(n)_  | _O(n)_ | Easy || Freq Table\n3078 | [Match Alphanumerical Pattern in Matrix I](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fmatch-alphanumerical-pattern-in-matrix-i\u002F) | [C++](.\u002FC++\u002Fmatch-alphanumerical-pattern-in-matrix-i.cpp) [Python](.\u002FPython\u002Fmatch-alphanumerical-pattern-in-matrix-i.py) | _O(n * m * r * c)_  | _O(1)_ | Medium |🔒| Brute Force, Hash Table\n3083 | [Existence of a Substring in a String and Its Reverse](https:\u002F\u002Fleetcode.com\u002Fproblems\u002Fexistence-of-a-substring-in-a-string-and-its-reverse\u002F) | [C++](.\u002FC++\u002Fexistence-of-a-substring-in-a-string-and-its-reverse.cpp) [Python](.\u002FPython\u002Fexistence-of-a-substring-in-a-string-and-its-reverse.py) | _O(n)_  | _O(min(n, 26^2))_ | E","该项目提供了所有3928道LeetCode题目的Python和现代C++解法，并每周更新。核心功能包括全面覆盖算法与数据结构问题，使用了现代C++特性（如C++11及以上版本）来提供简洁高效的解决方案。项目特别适合于准备技术面试、提高编程技能以及深入学习算法与数据结构的开发者。无论是初学者还是经验丰富的程序员，都能从中找到适合自己水平的挑战题目。",2,"2026-06-11 03:32:21","trending"]