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
1954. Minimum Garden Perimeter to Collect Enough Apples	Medium	55.5%	Binary Search Math	Read
1958. Check if Move is Legal	Medium	50.0%	Array Enumeration+1	Read
1959. Minimum Total Space Wasted With K Resizing Operations	Medium	44.0%	Array Dynamic Programming	Read
1962. Remove Stones to Minimize the Total	Medium	66.2%	Array Greedy+1	Read
1963. Minimum Number of Swaps to Make the String Balanced	Medium	78.0%	Greedy Stack+2	Read
1966. Binary Searchable Numbers in an Unsorted Array	Medium	63.3%	Array Binary Search	Read
1968. Array With Elements Not Equal to Average of Neighbors	Medium	50.9%	Array Greedy+1	Read
1969. Minimum Non-Zero Product of the Array Elements	Medium	37.5%	Greedy Math+1	Read
1973. Count Nodes Equal to Sum of Descendants	Medium	77.4%	Binary Tree Depth-First Search+1	Read
1975. Maximum Matrix Sum	Medium	67.6%	Array Greedy+1	Read
1976. Number of Ways to Arrive at Destination	Medium	37.4%	Dynamic Programming Graph+2	Read
1980. Find Unique Binary String	Medium	81.2%	Array Backtracking+2	Read
1981. Minimize the Difference Between Target and Chosen Elements	Medium	36.8%	Array Dynamic Programming+1	Read
1983. Widest Pair of Indices With Equal Range Sum	Medium	54.0%	Array Hash Table+1	Read
1985. Find the Kth Largest Integer in the Array	Medium	48.3%	Array Divide and Conquer+4	Read
1986. Minimum Number of Work Sessions to Finish the Tasks	Medium	35.3%	Array Backtracking+3	Read
1988. Find Cutoff Score for Each School	Medium	66.8%	Database	Read
1989. Maximum Number of People That Can Be Caught in Tag	Medium	49.4%	Array Greedy	Read
1990. Count the Number of Experiments	Medium	49.1%	Database	Read
1992. Find All Groups of Farmland	Medium	75.6%	Array Breadth-First Search+2	Read
1993. Operations on Tree	Medium	45.7%	Array Breadth-First Search+4	Read
1996. The Number of Weak Characters in the Game	Medium	44.7%	Array Greedy+3	Read
1997. First Day Where You Have Been in All the Rooms	Medium	40.5%	Array Dynamic Programming	Read
1999. Smallest Greater Multiple Made of Two Digits	Medium	47.4%	Enumeration Math	Read
2001. Number of Pairs of Interchangeable Rectangles	Medium	53.1%	Array Counting+3	Read
2002. Maximum Product of the Length of Two Palindromic Subsequences	Medium	62.4%	Backtracking Bit Manipulation+3	Read
2007. Find Original Array From Doubled Array	Medium	40.5%	Array Greedy+2	Read
2008. Maximum Earnings From Taxi	Medium	46.9%	Array Binary Search+3	Read
2012. Sum of Beauty in the Array	Medium	51.8%	Array	Read
2013. Detect Squares	Medium	53.0%	Array Counting+2	Read
2015. Average Height of Buildings in Each Segment	Medium	57.9%	Array Greedy+2	Read
2017. Grid Game	Medium	60.9%	Array Matrix+1	Read
2018. Check if Word Can Be Placed In Crossword	Medium	50.7%	Array Enumeration+1	Read
2020. Number of Accounts That Did Not Stream	Medium	72.0%	Database	Read
2021. Brightest Position on Street	Medium	60.5%	Array Ordered Set+1	Read
2023. Number of Pairs of Strings With Concatenation Equal to Target	Medium	75.1%	Array Counting+2	Read
2024. Maximize the Confusion of an Exam	Medium	70.4%	Binary Search Prefix Sum+2	Read
2028. Find Missing Observations	Medium	57.5%	Array Math+1	Read
2029. Stone Game IX	Medium	57.6%	Array Counting+3	Read
2031. Count Subarrays With More Ones Than Zeros	Medium	49.7%	Array Binary Indexed Tree+5	Read
2033. Minimum Operations to Make a Uni-Value Grid	Medium	70.7%	Array Math+2	Read
2034. Stock Price Fluctuation	Medium	49.1%	Data Stream Design+3	Read
2036. Maximum Alternating Subarray Sum	Medium	40.0%	Array Dynamic Programming	Read
2038. Remove Colored Pieces if Both Neighbors are the Same Color	Medium	62.8%	Game Theory Greedy+2	Read
2039. The Time When the Network Becomes Idle	Medium	56.1%	Array Breadth-First Search+1	Read
2041. Accepted Candidates From the Interviews	Medium	78.5%	Database	Read
2043. Simple Bank System	Medium	69.7%	Array Design+2	Read
2044. Count Number of Maximum Bitwise-OR Subsets	Medium	89.5%	Array Backtracking+2	Read
2046. Sort Linked List Already Sorted Using Absolute Values	Medium	67.1%	Linked List Sorting+1	Read
2048. Next Greater Numerically Balanced Number	Medium	63.1%	Backtracking Enumeration+1	Read

#1954Medium

Minimum Garden Perimeter to Collect Enough Apples

Binary SearchMath

Acceptance: 55.5%

#1958Medium

Check if Move is Legal

ArrayEnumerationMatrix

Acceptance: 50.0%

#1959Medium

Minimum Total Space Wasted With K Resizing Operations

ArrayDynamic Programming

Acceptance: 44.0%

#1962Medium

Remove Stones to Minimize the Total

ArrayGreedyHeap (Priority Queue)

Acceptance: 66.2%

#1963Medium

Minimum Number of Swaps to Make the String Balanced

GreedyStackString+1

Acceptance: 78.0%

#1966Medium

Binary Searchable Numbers in an Unsorted Array

ArrayBinary Search

Acceptance: 63.3%

#1968Medium

Array With Elements Not Equal to Average of Neighbors

ArrayGreedySorting

Acceptance: 50.9%

#1969Medium

Minimum Non-Zero Product of the Array Elements

GreedyMathRecursion

Acceptance: 37.5%

#1973Medium

Count Nodes Equal to Sum of Descendants

Binary TreeDepth-First SearchTree

Acceptance: 77.4%

#1975Medium

Maximum Matrix Sum

ArrayGreedyMatrix

Acceptance: 67.6%

#1976Medium

Number of Ways to Arrive at Destination

Dynamic ProgrammingGraphShortest Path+1

Acceptance: 37.4%

#1980Medium

Find Unique Binary String

ArrayBacktrackingHash Table+1

Acceptance: 81.2%

#1981Medium

Minimize the Difference Between Target and Chosen Elements

ArrayDynamic ProgrammingMatrix

Acceptance: 36.8%

#1983Medium

Widest Pair of Indices With Equal Range Sum

ArrayHash TablePrefix Sum

Acceptance: 54.0%

#1985Medium

Find the Kth Largest Integer in the Array

ArrayDivide and ConquerHeap (Priority Queue)+3

Acceptance: 48.3%

#1986Medium

Minimum Number of Work Sessions to Finish the Tasks

ArrayBacktrackingBit Manipulation+2

Acceptance: 35.3%

#1988Medium

Find Cutoff Score for Each School

Database

Acceptance: 66.8%

#1989Medium

Maximum Number of People That Can Be Caught in Tag

ArrayGreedy

Acceptance: 49.4%

#1990Medium

Count the Number of Experiments

Database

Acceptance: 49.1%

#1992Medium

Find All Groups of Farmland

ArrayBreadth-First SearchDepth-First Search+1

Acceptance: 75.6%

#1993Medium

Operations on Tree

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 45.7%

#1996Medium

The Number of Weak Characters in the Game

ArrayGreedyMonotonic Stack+2

Acceptance: 44.7%

#1997Medium

First Day Where You Have Been in All the Rooms

ArrayDynamic Programming

Acceptance: 40.5%

#1999Medium

Smallest Greater Multiple Made of Two Digits

EnumerationMath

Acceptance: 47.4%

#2001Medium

Number of Pairs of Interchangeable Rectangles

ArrayCountingHash Table+2

Acceptance: 53.1%

#2002Medium

Maximum Product of the Length of Two Palindromic Subsequences

BacktrackingBit ManipulationBitmask+2

Acceptance: 62.4%

#2007Medium

Find Original Array From Doubled Array

ArrayGreedyHash Table+1

Acceptance: 40.5%

#2008Medium

Maximum Earnings From Taxi

ArrayBinary SearchDynamic Programming+2

Acceptance: 46.9%

#2012Medium

Sum of Beauty in the Array

Array

Acceptance: 51.8%

#2013Medium

Detect Squares

ArrayCountingDesign+1

Acceptance: 53.0%

#2015Medium

Average Height of Buildings in Each Segment

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 57.9%

#2017Medium

Grid Game

ArrayMatrixPrefix Sum

Acceptance: 60.9%

#2018Medium

Check if Word Can Be Placed In Crossword

ArrayEnumerationMatrix

Acceptance: 50.7%

#2020Medium

Number of Accounts That Did Not Stream

Database

Acceptance: 72.0%

#2021Medium

Brightest Position on Street

ArrayOrdered SetPrefix Sum

Acceptance: 60.5%

#2023Medium

Number of Pairs of Strings With Concatenation Equal to Target

ArrayCountingHash Table+1

Acceptance: 75.1%

#2024Medium

Maximize the Confusion of an Exam

Binary SearchPrefix SumSliding Window+1

Acceptance: 70.4%

#2028Medium

Find Missing Observations

ArrayMathSimulation

Acceptance: 57.5%

#2029Medium

Stone Game IX

ArrayCountingGame Theory+2

Acceptance: 57.6%

#2031Medium

Count Subarrays With More Ones Than Zeros

ArrayBinary Indexed TreeBinary Search+4

Acceptance: 49.7%

#2033Medium

Minimum Operations to Make a Uni-Value Grid

ArrayMathMatrix+1

Acceptance: 70.7%

#2034Medium

Stock Price Fluctuation

Data StreamDesignHash Table+2

Acceptance: 49.1%

#2036Medium

Maximum Alternating Subarray Sum

ArrayDynamic Programming

Acceptance: 40.0%

#2038Medium

Remove Colored Pieces if Both Neighbors are the Same Color

Game TheoryGreedyMath+1

Acceptance: 62.8%

#2039Medium

The Time When the Network Becomes Idle

ArrayBreadth-First SearchGraph

Acceptance: 56.1%

#2041Medium

Accepted Candidates From the Interviews

Database

Acceptance: 78.5%

#2043Medium

Simple Bank System

ArrayDesignHash Table+1

Acceptance: 69.7%

#2044Medium

Count Number of Maximum Bitwise-OR Subsets

ArrayBacktrackingBit Manipulation+1

Acceptance: 89.5%

#2046Medium

Sort Linked List Already Sorted Using Absolute Values

Linked ListSortingTwo Pointers

Acceptance: 67.1%

#2048Medium

Next Greater Numerically Balanced Number

BacktrackingEnumerationMath

Acceptance: 63.1%

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