Solutions & Explanations

Browse 4,030+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,030 Solutions961 Easy2102 Medium967 Hard

Title	Difficulty	Acceptance	Topics	Solution
1864. Minimum Number of Swaps to Make the Binary String Alternating	Medium	44.1%	Greedy String	Read
1865. Finding Pairs With a Certain Sum	Medium	61.6%	Array Design+1	Read
1867. Orders With Maximum Quantity Above Average	Medium	70.8%	Database	Read
1868. Product of Two Run-Length Encoded Arrays	Medium	59.6%	Array Two Pointers	Read
1870. Minimum Speed to Arrive on Time	Medium	47.7%	Array Binary Search	Read
1871. Jump Game VII	Medium	35.4%	Dynamic Programming Prefix Sum+2	Read
1874. Minimize Product Sum of Two Arrays	Medium	89.5%	Array Greedy+1	Read
1875. Group Employees of the Same Salary	Medium	66.9%	Database	Read
1877. Minimize Maximum Pair Sum in Array	Medium	83.3%	Array Greedy+2	Read
1878. Get Biggest Three Rhombus Sums in a Grid	Medium	71.4%	Array Heap (Priority Queue)+4	Read
1881. Maximum Value after Insertion	Medium	39.3%	Greedy String	Read
1882. Process Tasks Using Servers	Medium	42.0%	Array Heap (Priority Queue)	Read
1884. Egg Drop With 2 Eggs and N Floors	Medium	74.6%	Dynamic Programming Math	Read
1885. Count Pairs in Two Arrays	Medium	60.5%	Array Binary Search+2	Read
1887. Reduction Operations to Make the Array Elements Equal	Medium	72.7%	Array Sorting	Read
1888. Minimum Number of Flips to Make the Binary String Alternating	Medium	53.5%	Dynamic Programming Greedy+2	Read
1891. Cutting Ribbons	Medium	53.0%	Array Binary Search	Read
1894. Find the Student that Will Replace the Chalk	Medium	53.2%	Array Binary Search+2	Read
1895. Largest Magic Square	Medium	75.3%	Array Matrix+1	Read
1898. Maximum Number of Removable Characters	Medium	47.6%	Array Binary Search+2	Read
1899. Merge Triplets to Form Target Triplet	Medium	69.5%	Array Greedy	Read
1901. Find a Peak Element II	Medium	55.7%	Array Binary Search+1	Read
1902. Depth of BST Given Insertion Order	Medium	42.5%	Array Binary Search Tree+3	Read
1904. The Number of Full Rounds You Have Played	Medium	43.9%	Math String	Read
1905. Count Sub Islands	Medium	72.8%	Array Breadth-First Search+3	Read
1906. Minimum Absolute Difference Queries	Medium	45.8%	Array Hash Table	Read
1907. Count Salary Categories	Medium	62.5%	Database	Read
1908. Game of Nim	Medium	62.4%	Array Bit Manipulation+4	Read
1910. Remove All Occurrences of a Substring	Medium	78.2%	Simulation Stack+1	Read
1911. Maximum Alternating Subsequence Sum	Medium	58.8%	Array Dynamic Programming	Read
1914. Cyclically Rotating a Grid	Medium	74.2%	Array Matrix+1	Read
1915. Number of Wonderful Substrings	Medium	66.8%	Bit Manipulation Hash Table+2	Read
1918. Kth Smallest Subarray Sum	Medium	53.4%	Array Binary Search+1	Read
1921. Eliminate Maximum Number of Monsters	Medium	50.9%	Array Greedy+1	Read
1922. Count Good Numbers	Medium	58.1%	Math Recursion	Read
1926. Nearest Exit from Entrance in Maze	Medium	49.0%	Array Breadth-First Search+1	Read
1927. Sum Game	Medium	63.5%	Game Theory Greedy+2	Read
1930. Unique Length-3 Palindromic Subsequences	Medium	73.8%	Bit Manipulation Hash Table+2	Read
1934. Confirmation Rate	Medium	60.1%	Database	Read
1936. Add Minimum Number of Rungs	Medium	43.8%	Array Greedy	Read
1937. Maximum Number of Points with Cost	Medium	41.8%	Array Dynamic Programming+1	Read
1940. Longest Common Subsequence Between Sorted Arrays	Medium	81.3%	Array Counting+1	Read
1942. The Number of the Smallest Unoccupied Chair	Medium	60.3%	Array Hash Table+1	Read
1943. Describe the Painting	Medium	52.7%	Array Hash Table+2	Read
1946. Largest Number After Mutating Substring	Medium	38.5%	Array Greedy+1	Read
1947. Maximum Compatibility Score Sum	Medium	65.0%	Array Backtracking+3	Read
1949. Strong Friendship	Medium	54.6%	Database	Read
1950. Maximum of Minimum Values in All Subarrays	Medium	48.0%	Array Monotonic Stack+1	Read
1951. All the Pairs With the Maximum Number of Common Followers	Medium	68.9%	Database	Read
1953. Maximum Number of Weeks for Which You Can Work	Medium	42.4%	Array Greedy	Read

#1864Medium

Minimum Number of Swaps to Make the Binary String Alternating

GreedyString

Acceptance: 44.1%

#1865Medium

Finding Pairs With a Certain Sum

ArrayDesignHash Table

Acceptance: 61.6%

#1867Medium

Orders With Maximum Quantity Above Average

Database

Acceptance: 70.8%

#1868Medium

Product of Two Run-Length Encoded Arrays

ArrayTwo Pointers

Acceptance: 59.6%

#1870Medium

Minimum Speed to Arrive on Time

ArrayBinary Search

Acceptance: 47.7%

#1871Medium

Jump Game VII

Dynamic ProgrammingPrefix SumSliding Window+1

Acceptance: 35.4%

#1874Medium

Minimize Product Sum of Two Arrays

ArrayGreedySorting

Acceptance: 89.5%

#1875Medium

Group Employees of the Same Salary

Database

Acceptance: 66.9%

#1877Medium

Minimize Maximum Pair Sum in Array

ArrayGreedySorting+1

Acceptance: 83.3%

#1878Medium

Get Biggest Three Rhombus Sums in a Grid

ArrayHeap (Priority Queue)Math+3

Acceptance: 71.4%

#1881Medium

Maximum Value after Insertion

GreedyString

Acceptance: 39.3%

#1882Medium

Process Tasks Using Servers

ArrayHeap (Priority Queue)

Acceptance: 42.0%

#1884Medium

Egg Drop With 2 Eggs and N Floors

Dynamic ProgrammingMath

Acceptance: 74.6%

#1885Medium

Count Pairs in Two Arrays

ArrayBinary SearchSorting+1

Acceptance: 60.5%

#1887Medium

Reduction Operations to Make the Array Elements Equal

ArraySorting

Acceptance: 72.7%

#1888Medium

Minimum Number of Flips to Make the Binary String Alternating

Dynamic ProgrammingGreedySliding Window+1

Acceptance: 53.5%

#1891Medium

Cutting Ribbons

ArrayBinary Search

Acceptance: 53.0%

#1894Medium

Find the Student that Will Replace the Chalk

ArrayBinary SearchPrefix Sum+1

Acceptance: 53.2%

#1895Medium

Largest Magic Square

ArrayMatrixPrefix Sum

Acceptance: 75.3%

#1898Medium

Maximum Number of Removable Characters

ArrayBinary SearchString+1

Acceptance: 47.6%

#1899Medium

Merge Triplets to Form Target Triplet

ArrayGreedy

Acceptance: 69.5%

#1901Medium

Find a Peak Element II

ArrayBinary SearchMatrix

Acceptance: 55.7%

#1902Medium

Depth of BST Given Insertion Order

ArrayBinary Search TreeBinary Tree+2

Acceptance: 42.5%

#1904Medium

The Number of Full Rounds You Have Played

MathString

Acceptance: 43.9%

#1905Medium

Count Sub Islands

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 72.8%

#1906Medium

Minimum Absolute Difference Queries

ArrayHash Table

Acceptance: 45.8%

#1907Medium

Count Salary Categories

Database

Acceptance: 62.5%

#1908Medium

Game of Nim

ArrayBit ManipulationBrainteaser+3

Acceptance: 62.4%

#1910Medium

Remove All Occurrences of a Substring

SimulationStackString

Acceptance: 78.2%

#1911Medium

Maximum Alternating Subsequence Sum

ArrayDynamic Programming

Acceptance: 58.8%

#1914Medium

Cyclically Rotating a Grid

ArrayMatrixSimulation

Acceptance: 74.2%

#1915Medium

Number of Wonderful Substrings

Bit ManipulationHash TablePrefix Sum+1

Acceptance: 66.8%

#1918Medium

Kth Smallest Subarray Sum

ArrayBinary SearchSliding Window

Acceptance: 53.4%

#1921Medium

Eliminate Maximum Number of Monsters

ArrayGreedySorting

Acceptance: 50.9%

#1922Medium

Count Good Numbers

MathRecursion

Acceptance: 58.1%

#1926Medium

Nearest Exit from Entrance in Maze

ArrayBreadth-First SearchMatrix

Acceptance: 49.0%

#1927Medium

Sum Game

Game TheoryGreedyMath+1

Acceptance: 63.5%

#1930Medium

Unique Length-3 Palindromic Subsequences

Bit ManipulationHash TablePrefix Sum+1

Acceptance: 73.8%

#1934Medium

Confirmation Rate

Database

Acceptance: 60.1%

#1936Medium

Add Minimum Number of Rungs

ArrayGreedy

Acceptance: 43.8%

#1937Medium

Maximum Number of Points with Cost

ArrayDynamic ProgrammingMatrix

Acceptance: 41.8%

#1940Medium

Longest Common Subsequence Between Sorted Arrays

ArrayCountingHash Table

Acceptance: 81.3%

#1942Medium

The Number of the Smallest Unoccupied Chair

ArrayHash TableHeap (Priority Queue)

Acceptance: 60.3%

#1943Medium

Describe the Painting

ArrayHash TablePrefix Sum+1

Acceptance: 52.7%

#1946Medium

Largest Number After Mutating Substring

ArrayGreedyString

Acceptance: 38.5%

#1947Medium

Maximum Compatibility Score Sum

ArrayBacktrackingBit Manipulation+2

Acceptance: 65.0%

#1949Medium

Strong Friendship

Database

Acceptance: 54.6%

#1950Medium

Maximum of Minimum Values in All Subarrays

ArrayMonotonic StackStack

Acceptance: 48.0%

#1951Medium

All the Pairs With the Maximum Number of Common Followers

Database

Acceptance: 68.9%

#1953Medium

Maximum Number of Weeks for Which You Can Work

ArrayGreedy

Acceptance: 42.4%

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