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
900. RLE Iterator	Medium	59.6%	Array Counting+2	Read
901. Online Stock Span	Medium	69.5%	Data Stream Design+2	Read
904. Fruit Into Baskets	Medium	52.5%	Array Hash Table+1	Read
907. Sum of Subarray Minimums	Medium	39.0%	Array Dynamic Programming+2	Read
909. Snakes and Ladders	Medium	48.0%	Array Breadth-First Search+1	Read
910. Smallest Range II	Medium	37.8%	Array Greedy+2	Read
911. Online Election	Medium	52.8%	Array Binary Search+2	Read
912. Sort an Array	Medium	55.9%	Array Bucket Sort+6	Read
915. Partition Array into Disjoint Intervals	Medium	49.4%	Array	Read
916. Word Subsets	Medium	55.9%	Array Hash Table+1	Read
918. Maximum Sum Circular Subarray	Medium	51.5%	Array Divide and Conquer+3	Read
919. Complete Binary Tree Inserter	Medium	65.0%	Binary Tree Breadth-First Search+2	Read
921. Minimum Add to Make Parentheses Valid	Medium	74.7%	Greedy Stack+1	Read
923. 3Sum With Multiplicity	Medium	46.2%	Array Counting+3	Read
926. Flip String to Monotone Increasing	Medium	61.5%	Dynamic Programming String	Read
930. Binary Subarrays With Sum	Medium	69.7%	Array Hash Table+2	Read
931. Minimum Falling Path Sum	Medium	60.8%	Array Dynamic Programming+1	Read
932. Beautiful Array	Medium	70.1%	Array Divide and Conquer+1	Read
934. Shortest Bridge	Medium	59.3%	Array Breadth-First Search+2	Read
935. Knight Dialer	Medium	61.8%	Dynamic Programming	Read
937. Reorder Data in Log Files	Medium	56.6%	Array Sorting+1	Read
939. Minimum Area Rectangle	Medium	55.4%	Array Geometry+3	Read
945. Minimum Increment to Make Array Unique	Medium	60.7%	Array Counting+2	Read
946. Validate Stack Sequences	Medium	70.8%	Array Simulation+1	Read
947. Most Stones Removed with Same Row or Column	Medium	63.4%	Depth-First Search Graph+2	Read
948. Bag of Tokens	Medium	59.5%	Array Greedy+2	Read
949. Largest Time for Given Digits	Medium	36.0%	Array Enumeration+1	Read
950. Reveal Cards In Increasing Order	Medium	83.6%	Array Queue+2	Read
951. Flip Equivalent Binary Trees	Medium	69.8%	Binary Tree Depth-First Search+1	Read
954. Array of Doubled Pairs	Medium	39.7%	Array Greedy+2	Read
955. Delete Columns to Make Sorted II	Medium	49.7%	Array Greedy+1	Read
957. Prison Cells After N Days	Medium	39.0%	Array Bit Manipulation+2	Read
958. Check Completeness of a Binary Tree	Medium	59.0%	Binary Tree Breadth-First Search+1	Read
959. Regions Cut By Slashes	Medium	77.8%	Array Breadth-First Search+4	Read
962. Maximum Width Ramp	Medium	55.5%	Array Monotonic Stack+1	Read
963. Minimum Area Rectangle II	Medium	55.9%	Array Geometry+1	Read
966. Vowel Spellchecker	Medium	61.4%	Array Hash Table+1	Read
967. Numbers With Same Consecutive Differences	Medium	59.1%	Backtracking Breadth-First Search	Read
969. Pancake Sorting	Medium	71.7%	Array Greedy+2	Read
970. Powerful Integers	Medium	44.5%	Enumeration Hash Table+1	Read
971. Flip Binary Tree To Match Preorder Traversal	Medium	51.9%	Binary Tree Depth-First Search+1	Read
973. K Closest Points to Origin	Medium	69.4%	Array Divide and Conquer+5	Read
974. Subarray Sums Divisible by K	Medium	56.7%	Array Hash Table+1	Read
978. Longest Turbulent Subarray	Medium	49.0%	Array Dynamic Programming+1	Read
979. Distribute Coins in Binary Tree	Medium	77.2%	Binary Tree Depth-First Search+1	Read
981. Time Based Key-Value Store	Medium	49.8%	Binary Search Design+2	Read
983. Minimum Cost For Tickets	Medium	67.4%	Array Dynamic Programming	Read
984. String Without AAA or BBB	Medium	45.6%	Greedy String	Read
985. Sum of Even Numbers After Queries	Medium	68.8%	Array Simulation	Read
986. Interval List Intersections	Medium	73.0%	Array Two Pointers	Read

#900Medium

RLE Iterator

ArrayCountingDesign+1

Acceptance: 59.6%

#901Medium

Online Stock Span

Data StreamDesignMonotonic Stack+1

Acceptance: 69.5%

#904Medium

Fruit Into Baskets

ArrayHash TableSliding Window

Acceptance: 52.5%

#907Medium

Sum of Subarray Minimums

ArrayDynamic ProgrammingMonotonic Stack+1

Acceptance: 39.0%

#909Medium

Snakes and Ladders

ArrayBreadth-First SearchMatrix

Acceptance: 48.0%

#910Medium

Smallest Range II

ArrayGreedyMath+1

Acceptance: 37.8%

#911Medium

Online Election

ArrayBinary SearchDesign+1

Acceptance: 52.8%

#912Medium

Sort an Array

ArrayBucket SortCounting Sort+5

Acceptance: 55.9%

#915Medium

Partition Array into Disjoint Intervals

Array

Acceptance: 49.4%

#916Medium

Word Subsets

ArrayHash TableString

Acceptance: 55.9%

#918Medium

Maximum Sum Circular Subarray

ArrayDivide and ConquerDynamic Programming+2

Acceptance: 51.5%

#919Medium

Complete Binary Tree Inserter

Binary TreeBreadth-First SearchDesign+1

Acceptance: 65.0%

#921Medium

Minimum Add to Make Parentheses Valid

GreedyStackString

Acceptance: 74.7%

#923Medium

3Sum With Multiplicity

ArrayCountingHash Table+2

Acceptance: 46.2%

#926Medium

Flip String to Monotone Increasing

Dynamic ProgrammingString

Acceptance: 61.5%

#930Medium

Binary Subarrays With Sum

ArrayHash TablePrefix Sum+1

Acceptance: 69.7%

#931Medium

Minimum Falling Path Sum

ArrayDynamic ProgrammingMatrix

Acceptance: 60.8%

#932Medium

Beautiful Array

ArrayDivide and ConquerMath

Acceptance: 70.1%

#934Medium

Shortest Bridge

ArrayBreadth-First SearchDepth-First Search+1

Acceptance: 59.3%

#935Medium

Knight Dialer

Dynamic Programming

Acceptance: 61.8%

#937Medium

Reorder Data in Log Files

ArraySortingString

Acceptance: 56.6%

#939Medium

Minimum Area Rectangle

ArrayGeometryHash Table+2

Acceptance: 55.4%

#945Medium

Minimum Increment to Make Array Unique

ArrayCountingGreedy+1

Acceptance: 60.7%

#946Medium

Validate Stack Sequences

ArraySimulationStack

Acceptance: 70.8%

#947Medium

Most Stones Removed with Same Row or Column

Depth-First SearchGraphHash Table+1

Acceptance: 63.4%

#948Medium

Bag of Tokens

ArrayGreedySorting+1

Acceptance: 59.5%

#949Medium

Largest Time for Given Digits

ArrayEnumerationString

Acceptance: 36.0%

#950Medium

Reveal Cards In Increasing Order

ArrayQueueSimulation+1

Acceptance: 83.6%

#951Medium

Flip Equivalent Binary Trees

Binary TreeDepth-First SearchTree

Acceptance: 69.8%

#954Medium

Array of Doubled Pairs

ArrayGreedyHash Table+1

Acceptance: 39.7%

#955Medium

Delete Columns to Make Sorted II

ArrayGreedyString

Acceptance: 49.7%

#957Medium

Prison Cells After N Days

ArrayBit ManipulationHash Table+1

Acceptance: 39.0%

#958Medium

Check Completeness of a Binary Tree

Binary TreeBreadth-First SearchTree

Acceptance: 59.0%

#959Medium

Regions Cut By Slashes

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 77.8%

#962Medium

Maximum Width Ramp

ArrayMonotonic StackStack

Acceptance: 55.5%

#963Medium

Minimum Area Rectangle II

ArrayGeometryMath

Acceptance: 55.9%

#966Medium

Vowel Spellchecker

ArrayHash TableString

Acceptance: 61.4%

#967Medium

Numbers With Same Consecutive Differences

BacktrackingBreadth-First Search

Acceptance: 59.1%

#969Medium

Pancake Sorting

ArrayGreedySorting+1

Acceptance: 71.7%

#970Medium

Powerful Integers

EnumerationHash TableMath

Acceptance: 44.5%

#971Medium

Flip Binary Tree To Match Preorder Traversal

Binary TreeDepth-First SearchTree

Acceptance: 51.9%

#973Medium

K Closest Points to Origin

ArrayDivide and ConquerGeometry+4

Acceptance: 69.4%

#974Medium

Subarray Sums Divisible by K

ArrayHash TablePrefix Sum

Acceptance: 56.7%

#978Medium

Longest Turbulent Subarray

ArrayDynamic ProgrammingSliding Window

Acceptance: 49.0%

#979Medium

Distribute Coins in Binary Tree

Binary TreeDepth-First SearchTree

Acceptance: 77.2%

#981Medium

Time Based Key-Value Store

Binary SearchDesignHash Table+1

Acceptance: 49.8%

#983Medium

Minimum Cost For Tickets

ArrayDynamic Programming

Acceptance: 67.4%

#984Medium

String Without AAA or BBB

GreedyString

Acceptance: 45.6%

#985Medium

Sum of Even Numbers After Queries

ArraySimulation

Acceptance: 68.8%

#986Medium

Interval List Intersections

ArrayTwo Pointers

Acceptance: 73.0%

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