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
4031. Find All Numbers Disappeared in an Array II	Medium	52.8%	Array Binary Search+1	Read
4032. Longest Subarray With at Most K Distinct Prime Factors	Medium	56.5%	Array Hash Table+3	Read
4033. Valid K-Unique Subarrays I	Hard	34.8%	Array Binary Indexed Tree+4	Read
4034. Minimum Bishop Moves to Reach Target	Medium	65.4%	Array Math	Read
4037. Maximum Valid Split Positions II	Hard	31.6%	Array Enumeration+2	Read
4035. Maximum Valid Split Positions I	Medium	51.8%	Array Enumeration+2	Read
4036. Lexicographically Largest String After Pair Transformations	Medium	42.2%	Array Bit Manipulation+2	Read
4038. Count Integers Appearing in a Single Block	Easy	44.4%	Array Counting+1	Read
4039. Sum of Decoded Numbers	Medium	44.8%	Array Math+1	Read
4041. Minimum Operations to Form Subset Sum II	Hard	49.3%	Array Dynamic Programming	Read
4040. Minimum Operations to Form Subset Sum I	Medium	52.4%	Array Dynamic Programming	Read
4042. Valid K-Unique Subarrays II	Hard	68.8%		Read
4044. Count Good Cyclic Rotations	Medium	49.0%	Array Prefix Sum+1	Read
4043. Count Rotations With Exactly K Equal Adjacent Pairs	Easy	71.7%	Enumeration Sliding Window+1	Read
4045. Count Robot Groups	Medium	31.3%	Array Monotonic Stack+1	Read
4046. Minimum Cost Path With At Most K Turns	Hard	53.9%	Array Graph+3	Read
4047. Minimum Operations to Make XOR of All Elements Zero	Hard	55.9%		Read
4048. Count Values With Equally Spaced Occurrences I	Easy	74.7%	Array Hash Table	Read
4049. Count Values With Equally Spaced Occurrences II	Medium	62.3%	Array Hash Table	Read
4050. Minimum Days to Score Exactly N Points	Medium	41.6%	Dynamic Programming Math	Read
4051. Count Subarrays with Distant Sums	Hard	32.2%	Array Binary Indexed Tree+3	Read
4052. Cyclically Shift Rows and Columns	Easy	75.9%	Array Matrix+1	Read
4053. Minimum Operations to Make Every Element Palindromic	Medium	14.9%	Array Binary Search	Read
4054. Count Shadow Pairs I	Medium	41.2%	Array Monotonic Stack+1	Read
4055. Count Shadow Pairs II	Hard	16.9%	Array Binary Indexed Tree+6	Read
4056. Number of Intersecting Interval Pairs I	Easy	61.2%		Read
4057. Number of Intersecting Interval Pairs II	Medium	50.3%		Read
4058. Maximum Pulse Value After One Subarray Rotation	Medium	37.6%		Read
4059. Lexicographically Largest Power Array	Hard	21.6%		Read

#4031Medium

Find All Numbers Disappeared in an Array II

ArrayBinary SearchSorting

Acceptance: 52.8%

#4032Medium

Longest Subarray With at Most K Distinct Prime Factors

ArrayHash TableMath+2

Acceptance: 56.5%

#4033Hard

Valid K-Unique Subarrays I

ArrayBinary Indexed TreeBit Manipulation+3

Acceptance: 34.8%

#4034Medium

Minimum Bishop Moves to Reach Target

ArrayMath

Acceptance: 65.4%

#4037Hard

Maximum Valid Split Positions II

ArrayEnumerationMath+1

Acceptance: 31.6%

#4035Medium

Maximum Valid Split Positions I

ArrayEnumerationMath+1

Acceptance: 51.8%

#4036Medium

Lexicographically Largest String After Pair Transformations

ArrayBit ManipulationGreedy+1

Acceptance: 42.2%

#4038Easy

Count Integers Appearing in a Single Block

ArrayCountingHash Table

Acceptance: 44.4%

#4039Medium

Sum of Decoded Numbers

ArrayMathSimulation

Acceptance: 44.8%

#4041Hard

Minimum Operations to Form Subset Sum II

ArrayDynamic Programming

Acceptance: 49.3%

#4040Medium

Minimum Operations to Form Subset Sum I

ArrayDynamic Programming

Acceptance: 52.4%

#4042Hard

Valid K-Unique Subarrays II

Acceptance: 68.8%

#4044Medium

Count Good Cyclic Rotations

ArrayPrefix SumSliding Window

Acceptance: 49.0%

#4043Easy

Count Rotations With Exactly K Equal Adjacent Pairs

EnumerationSliding WindowString

Acceptance: 71.7%

#4045Medium

Count Robot Groups

ArrayMonotonic StackStack

Acceptance: 31.3%

#4046Hard

Minimum Cost Path With At Most K Turns

ArrayGraphHeap+2

Acceptance: 53.9%

#4047Hard

Minimum Operations to Make XOR of All Elements Zero

Acceptance: 55.9%

#4048Easy

Count Values With Equally Spaced Occurrences I

ArrayHash Table

Acceptance: 74.7%

#4049Medium

Count Values With Equally Spaced Occurrences II

ArrayHash Table

Acceptance: 62.3%

#4050Medium

Minimum Days to Score Exactly N Points

Dynamic ProgrammingMath

Acceptance: 41.6%

#4051Hard

Count Subarrays with Distant Sums

ArrayBinary Indexed TreeBinary Search+2

Acceptance: 32.2%

#4052Easy

Cyclically Shift Rows and Columns

ArrayMatrixSimulation

Acceptance: 75.9%

#4053Medium

Minimum Operations to Make Every Element Palindromic

ArrayBinary Search

Acceptance: 14.9%

#4054Medium

Count Shadow Pairs I

ArrayMonotonic StackStack

Acceptance: 41.2%

#4055Hard

Count Shadow Pairs II

ArrayBinary Indexed TreeBinary Search+5

Acceptance: 16.9%

#4056Easy

Number of Intersecting Interval Pairs I

Acceptance: 61.2%

#4057Medium

Number of Intersecting Interval Pairs II

Acceptance: 50.3%

#4058Medium

Maximum Pulse Value After One Subarray Rotation

Acceptance: 37.6%

#4059Hard

Lexicographically Largest Power Array

Acceptance: 21.6%

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