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
2051. The Category of Each Member in the Store	Medium	70.2%	Database	Read
2052. Minimum Cost to Separate Sentence Into Rows	Medium	50.1%	Array Dynamic Programming	Read
2053. Kth Distinct String in an Array	Easy	82.1%	Array Counting+2	Read
2054. Two Best Non-Overlapping Events	Medium	64.0%	Array Binary Search+3	Read
2055. Plates Between Candles	Medium	47.4%	Array Binary Search+2	Read
2056. Number of Valid Move Combinations On Chessboard	Hard	48.1%	Array Backtracking+2	Read
2057. Smallest Index With Equal Value	Easy	73.8%	Array	Read
2058. Find the Minimum and Maximum Number of Nodes Between Critical Points	Medium	72.9%	Linked List	Read
2059. Minimum Operations to Convert Number	Medium	52.3%	Array Breadth-First Search	Read
2060. Check if an Original String Exists Given Two Encoded Strings	Hard	43.6%	Dynamic Programming String	Read
2061. Number of Spaces Cleaning Robot Cleaned	Medium	64.3%	Array Matrix+1	Read
2062. Count Vowel Substrings of a String	Easy	73.6%	Hash Table String	Read
2063. Vowels of All Substrings	Medium	55.3%	Combinatorics Dynamic Programming+2	Read
2064. Minimized Maximum of Products Distributed to Any Store	Medium	63.1%	Array Binary Search+1	Read
2065. Maximum Path Quality of a Graph	Hard	63.1%	Array Backtracking+1	Read
2066. Account Balance	Medium	82.1%	Database	Read
2067. Number of Equal Count Substrings	Medium	45.1%	Counting Prefix Sum+1	Read
2068. Check Whether Two Strings are Almost Equivalent	Easy	64.5%	Counting Hash Table+1	Read
2069. Walking Robot Simulation II	Medium	43.2%	Design Simulation	Read
2070. Most Beautiful Item for Each Query	Medium	62.2%	Array Binary Search+1	Read
2071. Maximum Number of Tasks You Can Assign	Hard	50.1%	Array Binary Search+4	Read
2072. The Winner University	Easy	74.5%	Database	Read
2073. Time Needed to Buy Tickets	Easy	72.9%	Array Queue+1	Read
2074. Reverse Nodes in Even Length Groups	Medium	65.0%	Linked List	Read
2075. Decode the Slanted Ciphertext	Medium	67.3%	Simulation String	Read
2076. Process Restricted Friend Requests	Hard	61.7%	Graph Union Find	Read
2077. Paths in Maze That Lead to Same Room	Medium	56.7%	Graph	Read
2078. Two Furthest Houses With Different Colors	Easy	71.8%	Array Greedy	Read
2079. Watering Plants	Medium	79.9%	Array Simulation	Read
2080. Range Frequency Queries	Medium	44.3%	Array Binary Search+3	Read
2081. Sum of k-Mirror Numbers	Hard	63.7%	Enumeration Math	Read
2082. The Number of Rich Customers	Easy	77.3%	Database	Read
2083. Substrings That Begin and End With the Same Letter	Medium	74.1%	Counting Hash Table+3	Read
2084. Drop Type 1 Orders for Customers With Type 0 Orders	Medium	86.9%	Database	Read
2085. Count Common Words With One Occurrence	Easy	73.3%	Array Counting+2	Read
2086. Minimum Number of Food Buckets to Feed the Hamsters	Medium	48.1%	Dynamic Programming Greedy+1	Read
2087. Minimum Cost Homecoming of a Robot in a Grid	Medium	51.7%	Array Greedy	Read
2088. Count Fertile Pyramids in a Land	Hard	66.5%	Array Dynamic Programming+1	Read
2089. Find Target Indices After Sorting Array	Easy	77.9%	Array Binary Search+1	Read
2090. K Radius Subarray Averages	Medium	46.0%	Array Sliding Window	Read
2091. Removing Minimum and Maximum From Array	Medium	67.5%	Array Greedy	Read
2092. Find All People With Secret	Hard	48.4%	Breadth-First Search Depth-First Search+3	Read
2093. Minimum Cost to Reach City With Discounts	Medium	61.0%	Graph Heap (Priority Queue)+1	Read
2094. Finding 3-Digit Even Numbers	Easy	78.8%	Array Enumeration+2	Read
2095. Delete the Middle Node of a Linked List	Medium	60.4%	Linked List Two Pointers	Read
2096. Step-By-Step Directions From a Binary Tree Node to Another	Medium	56.3%	Binary Tree Depth-First Search+2	Read
2097. Valid Arrangement of Pairs	Hard	66.5%	Depth-First Search Eulerian Circuit+1	Read
2098. Subsequence of Size K With the Largest Even Sum	Medium	35.5%	Array Greedy+1	Read
2099. Find Subsequence of Length K With the Largest Sum	Easy	57.4%	Array Hash Table+2	Read
2100. Find Good Days to Rob the Bank	Medium	52.1%	Array Dynamic Programming+1	Read

#2051Medium

The Category of Each Member in the Store

Database

Acceptance: 70.2%

#2052Medium

Minimum Cost to Separate Sentence Into Rows

ArrayDynamic Programming

Acceptance: 50.1%

#2053Easy

Kth Distinct String in an Array

ArrayCountingHash Table+1

Acceptance: 82.1%

#2054Medium

Two Best Non-Overlapping Events

ArrayBinary SearchDynamic Programming+2

Acceptance: 64.0%

#2055Medium

Plates Between Candles

ArrayBinary SearchPrefix Sum+1

Acceptance: 47.4%

#2056Hard

Number of Valid Move Combinations On Chessboard

ArrayBacktrackingSimulation+1

Acceptance: 48.1%

#2057Easy

Smallest Index With Equal Value

Array

Acceptance: 73.8%

#2058Medium

Find the Minimum and Maximum Number of Nodes Between Critical Points

Linked List

Acceptance: 72.9%

#2059Medium

Minimum Operations to Convert Number

ArrayBreadth-First Search

Acceptance: 52.3%

#2060Hard

Check if an Original String Exists Given Two Encoded Strings

Dynamic ProgrammingString

Acceptance: 43.6%

#2061Medium

Number of Spaces Cleaning Robot Cleaned

ArrayMatrixSimulation

Acceptance: 64.3%

#2062Easy

Count Vowel Substrings of a String

Hash TableString

Acceptance: 73.6%

#2063Medium

Vowels of All Substrings

CombinatoricsDynamic ProgrammingMath+1

Acceptance: 55.3%

#2064Medium

Minimized Maximum of Products Distributed to Any Store

ArrayBinary SearchGreedy

Acceptance: 63.1%

#2065Hard

Maximum Path Quality of a Graph

ArrayBacktrackingGraph

Acceptance: 63.1%

#2066Medium

Account Balance

Database

Acceptance: 82.1%

#2067Medium

Number of Equal Count Substrings

CountingPrefix SumString

Acceptance: 45.1%

#2068Easy

Check Whether Two Strings are Almost Equivalent

CountingHash TableString

Acceptance: 64.5%

#2069Medium

Walking Robot Simulation II

DesignSimulation

Acceptance: 43.2%

#2070Medium

Most Beautiful Item for Each Query

ArrayBinary SearchSorting

Acceptance: 62.2%

#2071Hard

Maximum Number of Tasks You Can Assign

ArrayBinary SearchGreedy+3

Acceptance: 50.1%

#2072Easy

The Winner University

Database

Acceptance: 74.5%

#2073Easy

Time Needed to Buy Tickets

ArrayQueueSimulation

Acceptance: 72.9%

#2074Medium

Reverse Nodes in Even Length Groups

Linked List

Acceptance: 65.0%

#2075Medium

Decode the Slanted Ciphertext

SimulationString

Acceptance: 67.3%

#2076Hard

Process Restricted Friend Requests

GraphUnion Find

Acceptance: 61.7%

#2077Medium

Paths in Maze That Lead to Same Room

Graph

Acceptance: 56.7%

#2078Easy

Two Furthest Houses With Different Colors

ArrayGreedy

Acceptance: 71.8%

#2079Medium

Watering Plants

ArraySimulation

Acceptance: 79.9%

#2080Medium

Range Frequency Queries

ArrayBinary SearchDesign+2

Acceptance: 44.3%

#2081Hard

Sum of k-Mirror Numbers

EnumerationMath

Acceptance: 63.7%

#2082Easy

The Number of Rich Customers

Database

Acceptance: 77.3%

#2083Medium

Substrings That Begin and End With the Same Letter

CountingHash TableMath+2

Acceptance: 74.1%

#2084Medium

Drop Type 1 Orders for Customers With Type 0 Orders

Database

Acceptance: 86.9%

#2085Easy

Count Common Words With One Occurrence

ArrayCountingHash Table+1

Acceptance: 73.3%

#2086Medium

Minimum Number of Food Buckets to Feed the Hamsters

Dynamic ProgrammingGreedyString

Acceptance: 48.1%

#2087Medium

Minimum Cost Homecoming of a Robot in a Grid

ArrayGreedy

Acceptance: 51.7%

#2088Hard

Count Fertile Pyramids in a Land

ArrayDynamic ProgrammingMatrix

Acceptance: 66.5%

#2089Easy

Find Target Indices After Sorting Array

ArrayBinary SearchSorting

Acceptance: 77.9%

#2090Medium

K Radius Subarray Averages

ArraySliding Window

Acceptance: 46.0%

#2091Medium

Removing Minimum and Maximum From Array

ArrayGreedy

Acceptance: 67.5%

#2092Hard

Find All People With Secret

Breadth-First SearchDepth-First SearchGraph+2

Acceptance: 48.4%

#2093Medium

Minimum Cost to Reach City With Discounts

GraphHeap (Priority Queue)Shortest Path

Acceptance: 61.0%

#2094Easy

Finding 3-Digit Even Numbers

ArrayEnumerationHash Table+1

Acceptance: 78.8%

#2095Medium

Delete the Middle Node of a Linked List

Linked ListTwo Pointers

Acceptance: 60.4%

#2096Medium

Step-By-Step Directions From a Binary Tree Node to Another

Binary TreeDepth-First SearchString+1

Acceptance: 56.3%

#2097Hard

Valid Arrangement of Pairs

Depth-First SearchEulerian CircuitGraph

Acceptance: 66.5%

#2098Medium

Subsequence of Size K With the Largest Even Sum

ArrayGreedySorting

Acceptance: 35.5%

#2099Easy

Find Subsequence of Length K With the Largest Sum

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 57.4%

#2100Medium

Find Good Days to Rob the Bank

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 52.1%

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Master DSA with Step-by-Step Solutions

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