Solutions & Explanations

Browse 4,029+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,029 Solutions961 Easy2102 Medium966 Hard

Title	Difficulty	Acceptance	Topics	Solution
772. Basic Calculator III	Hard	53.2%	Math Recursion+2	Read
773. Sliding Puzzle	Hard	74.3%	Array Backtracking+4	Read
774. Minimize Max Distance to Gas Station	Hard	53.9%	Array Binary Search	Read
778. Swim in Rising Water	Hard	68.3%	Array Binary Search+5	Read
780. Reaching Points	Hard	34.3%	Math	Read
782. Transform to Chessboard	Hard	51.3%	Array Bit Manipulation+2	Read
793. Preimage Size of Factorial Zeroes Function	Hard	47.4%	Binary Search Math	Read
798. Smallest Rotation with Highest Score	Hard	54.2%	Array Prefix Sum	Read
801. Minimum Swaps To Make Sequences Increasing	Hard	42.0%	Array Dynamic Programming	Read
803. Bricks Falling When Hit	Hard	37.7%	Array Matrix+1	Read
805. Split Array With Same Average	Hard	27.5%	Array Bit Manipulation+3	Read
810. Chalkboard XOR Game	Hard	66.7%	Array Bit Manipulation+3	Read
815. Bus Routes	Hard	47.3%	Array Breadth-First Search+1	Read
818. Race Car	Hard	44.7%	Dynamic Programming	Read
827. Making A Large Island	Hard	57.0%	Array Breadth-First Search+3	Read
828. Count Unique Characters of All Substrings of a Given String	Hard	53.5%	Dynamic Programming Hash Table+1	Read
829. Consecutive Numbers Sum	Hard	42.6%	Enumeration Math	Read
834. Sum of Distances in Tree	Hard	65.8%	Depth-First Search Dynamic Programming+2	Read
839. Similar String Groups	Hard	56.1%	Array Breadth-First Search+4	Read
843. Guess the Word	Hard	36.9%	Array Game Theory+3	Read
847. Shortest Path Visiting All Nodes	Hard	65.9%	Bit Manipulation Bitmask+3	Read
850. Rectangle Area II	Hard	56.7%	Array Line Sweep+2	Read
854. K-Similar Strings	Hard	41.3%	Breadth-First Search String	Read
857. Minimum Cost to Hire K Workers	Hard	63.5%	Array Greedy+2	Read
862. Shortest Subarray with Sum at Least K	Hard	32.7%	Array Binary Search+5	Read
864. Shortest Path to Get All Keys	Hard	55.0%	Array Bit Manipulation+2	Read
871. Minimum Number of Refueling Stops	Hard	41.8%	Array Dynamic Programming+2	Read
878. Nth Magical Number	Hard	37.1%	Binary Search Math	Read
879. Profitable Schemes	Hard	48.1%	Array Dynamic Programming	Read
882. Reachable Nodes In Subdivided Graph	Hard	52.5%	Graph Heap (Priority Queue)+1	Read
887. Super Egg Drop	Hard	30.6%	Binary Search Dynamic Programming+1	Read
891. Sum of Subsequence Widths	Hard	41.1%	Array Math+1	Read
895. Maximum Frequency Stack	Hard	67.1%	Design Hash Table+2	Read
899. Orderly Queue	Hard	66.8%	Math Sorting+1	Read
902. Numbers At Most N Given Digit Set	Hard	45.9%	Array Binary Search+3	Read
903. Valid Permutations for DI Sequence	Hard	56.3%	Dynamic Programming Prefix Sum+1	Read
906. Super Palindromes	Hard	39.9%	Enumeration Math	Read
913. Cat and Mouse	Hard	36.2%	Dynamic Programming Game Theory+4	Read
920. Number of Music Playlists	Hard	60.3%	Combinatorics Dynamic Programming+1	Read
924. Minimize Malware Spread	Hard	43.0%	Array Breadth-First Search+4	Read
927. Three Equal Parts	Hard	41.3%	Array Math	Read
928. Minimize Malware Spread II	Hard	46.2%	Array Breadth-First Search+4	Read
936. Stamping The Sequence	Hard	62.2%	Greedy Queue+2	Read
940. Distinct Subsequences II	Hard	56.7%	Dynamic Programming String	Read
943. Find the Shortest Superstring	Hard	45.8%	Array Bit Manipulation+3	Read
952. Largest Component Size by Common Factor	Hard	43.8%	Array Hash Table+3	Read
956. Tallest Billboard	Hard	52.0%	Array Dynamic Programming	Read
960. Delete Columns to Make Sorted III	Hard	72.7%	Array Dynamic Programming+1	Read
964. Least Operators to Express Number	Hard	48.3%	Dynamic Programming Math+1	Read
968. Binary Tree Cameras	Hard	47.7%	Binary Tree Depth-First Search+2	Read

#772Hard

Basic Calculator III

MathRecursionStack+1

Acceptance: 53.2%

#773Hard

Sliding Puzzle

ArrayBacktrackingBreadth-First Search+3

Acceptance: 74.3%

#774Hard

Minimize Max Distance to Gas Station

ArrayBinary Search

Acceptance: 53.9%

#778Hard

Swim in Rising Water

ArrayBinary SearchBreadth-First Search+4

Acceptance: 68.3%

#780Hard

Reaching Points

Math

Acceptance: 34.3%

#782Hard

Transform to Chessboard

ArrayBit ManipulationMath+1

Acceptance: 51.3%

#793Hard

Preimage Size of Factorial Zeroes Function

Binary SearchMath

Acceptance: 47.4%

#798Hard

Smallest Rotation with Highest Score

ArrayPrefix Sum

Acceptance: 54.2%

#801Hard

Minimum Swaps To Make Sequences Increasing

ArrayDynamic Programming

Acceptance: 42.0%

#803Hard

Bricks Falling When Hit

ArrayMatrixUnion Find

Acceptance: 37.7%

#805Hard

Split Array With Same Average

ArrayBit ManipulationBitmask+2

Acceptance: 27.5%

#810Hard

Chalkboard XOR Game

ArrayBit ManipulationBrainteaser+2

Acceptance: 66.7%

#815Hard

Bus Routes

ArrayBreadth-First SearchHash Table

Acceptance: 47.3%

#818Hard

Race Car

Dynamic Programming

Acceptance: 44.7%

#827Hard

Making A Large Island

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 57.0%

#828Hard

Count Unique Characters of All Substrings of a Given String

Dynamic ProgrammingHash TableString

Acceptance: 53.5%

#829Hard

Consecutive Numbers Sum

EnumerationMath

Acceptance: 42.6%

#834Hard

Sum of Distances in Tree

Depth-First SearchDynamic ProgrammingGraph+1

Acceptance: 65.8%

#839Hard

Similar String Groups

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 56.1%

#843Hard

Guess the Word

ArrayGame TheoryInteractive+2

Acceptance: 36.9%

#847Hard

Shortest Path Visiting All Nodes

Bit ManipulationBitmaskBreadth-First Search+2

Acceptance: 65.9%

#850Hard

Rectangle Area II

ArrayLine SweepOrdered Set+1

Acceptance: 56.7%

#854Hard

K-Similar Strings

Breadth-First SearchString

Acceptance: 41.3%

#857Hard

Minimum Cost to Hire K Workers

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 63.5%

#862Hard

Shortest Subarray with Sum at Least K

ArrayBinary SearchHeap (Priority Queue)+4

Acceptance: 32.7%

#864Hard

Shortest Path to Get All Keys

ArrayBit ManipulationBreadth-First Search+1

Acceptance: 55.0%

#871Hard

Minimum Number of Refueling Stops

ArrayDynamic ProgrammingGreedy+1

Acceptance: 41.8%

#878Hard

Nth Magical Number

Binary SearchMath

Acceptance: 37.1%

#879Hard

Profitable Schemes

ArrayDynamic Programming

Acceptance: 48.1%

#882Hard

Reachable Nodes In Subdivided Graph

GraphHeap (Priority Queue)Shortest Path

Acceptance: 52.5%

#887Hard

Super Egg Drop

Binary SearchDynamic ProgrammingMath

Acceptance: 30.6%

#891Hard

Sum of Subsequence Widths

ArrayMathSorting

Acceptance: 41.1%

#895Hard

Maximum Frequency Stack

DesignHash TableOrdered Set+1

Acceptance: 67.1%

#899Hard

Orderly Queue

MathSortingString

Acceptance: 66.8%

#902Hard

Numbers At Most N Given Digit Set

ArrayBinary SearchDynamic Programming+2

Acceptance: 45.9%

#903Hard

Valid Permutations for DI Sequence

Dynamic ProgrammingPrefix SumString

Acceptance: 56.3%

#906Hard

Super Palindromes

EnumerationMath

Acceptance: 39.9%

#913Hard

Cat and Mouse

Dynamic ProgrammingGame TheoryGraph+3

Acceptance: 36.2%

#920Hard

Number of Music Playlists

CombinatoricsDynamic ProgrammingMath

Acceptance: 60.3%

#924Hard

Minimize Malware Spread

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 43.0%

#927Hard

Three Equal Parts

ArrayMath

Acceptance: 41.3%

#928Hard

Minimize Malware Spread II

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 46.2%

#936Hard

Stamping The Sequence

GreedyQueueStack+1

Acceptance: 62.2%

#940Hard

Distinct Subsequences II

Dynamic ProgrammingString

Acceptance: 56.7%

#943Hard

Find the Shortest Superstring

ArrayBit ManipulationBitmask+2

Acceptance: 45.8%

#952Hard

Largest Component Size by Common Factor

ArrayHash TableMath+2

Acceptance: 43.8%

#956Hard

Tallest Billboard

ArrayDynamic Programming

Acceptance: 52.0%

#960Hard

Delete Columns to Make Sorted III

ArrayDynamic ProgrammingString

Acceptance: 72.7%

#964Hard

Least Operators to Express Number

Dynamic ProgrammingMathMemoization

Acceptance: 48.3%

#968Hard

Binary Tree Cameras

Binary TreeDepth-First SearchDynamic Programming+1

Acceptance: 47.7%

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