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
2049. Count Nodes With the Highest Score	Medium	52.6%	Array Binary Tree+2	Read
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
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
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
2061. Number of Spaces Cleaning Robot Cleaned	Medium	64.3%	Array Matrix+1	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
2066. Account Balance	Medium	82.1%	Database	Read
2067. Number of Equal Count Substrings	Medium	45.1%	Counting Prefix Sum+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
2074. Reverse Nodes in Even Length Groups	Medium	65.0%	Linked List	Read
2075. Decode the Slanted Ciphertext	Medium	67.3%	Simulation String	Read
2077. Paths in Maze That Lead to Same Room	Medium	56.7%	Graph	Read
2079. Watering Plants	Medium	79.9%	Array Simulation	Read
2080. Range Frequency Queries	Medium	44.3%	Array Binary Search+3	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
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
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
2093. Minimum Cost to Reach City With Discounts	Medium	61.0%	Graph Heap (Priority Queue)+1	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
2098. Subsequence of Size K With the Largest Even Sum	Medium	35.5%	Array Greedy+1	Read
2100. Find Good Days to Rob the Bank	Medium	52.1%	Array Dynamic Programming+1	Read
2101. Detonate the Maximum Bombs	Medium	50.0%	Array Breadth-First Search+4	Read
2104. Sum of Subarray Ranges	Medium	61.6%	Array Monotonic Stack+1	Read
2105. Watering Plants II	Medium	48.8%	Array Simulation+1	Read
2107. Number of Unique Flavors After Sharing K Candies	Medium	62.4%	Array Hash Table+1	Read
2109. Adding Spaces to a String	Medium	71.8%	Array Simulation+2	Read
2110. Number of Smooth Descent Periods of a Stock	Medium	67.7%	Array Dynamic Programming+1	Read
2112. The Airport With the Most Traffic	Medium	70.6%	Database	Read
2113. Elements in Array After Removing and Replacing Elements	Medium	69.1%	Array	Read
2115. Find All Possible Recipes from Given Supplies	Medium	56.8%	Array Graph+3	Read
2116. Check if a Parentheses String Can Be Valid	Medium	45.1%	Greedy Stack+1	Read
2120. Execution of All Suffix Instructions Staying in a Grid	Medium	82.4%	Simulation String	Read
2121. Intervals Between Identical Elements	Medium	47.8%	Array Hash Table+1	Read
2125. Number of Laser Beams in a Bank	Medium	87.0%	Array Math+2	Read
2126. Destroying Asteroids	Medium	59.7%	Array Greedy+1	Read
2128. Remove All Ones With Row and Column Flips	Medium	76.2%	Array Bit Manipulation+2	Read
2130. Maximum Twin Sum of a Linked List	Medium	83.2%	Linked List Stack+1	Read
2131. Longest Palindrome by Concatenating Two Letter Words	Medium	53.5%	Array Counting+3	Read
2134. Minimum Swaps to Group All 1's Together II	Medium	65.5%	Array Sliding Window	Read
2135. Count Words Obtained After Adding a Letter	Medium	44.0%	Array Bit Manipulation+3	Read
2137. Pour Water Between Buckets to Make Water Levels Equal	Medium	68.4%	Array Binary Search	Read

#2049Medium

Count Nodes With the Highest Score

ArrayBinary TreeDepth-First Search+1

Acceptance: 52.6%

#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%

#2054Medium

Two Best Non-Overlapping Events

ArrayBinary SearchDynamic Programming+2

Acceptance: 64.0%

#2055Medium

Plates Between Candles

ArrayBinary SearchPrefix Sum+1

Acceptance: 47.4%

#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%

#2061Medium

Number of Spaces Cleaning Robot Cleaned

ArrayMatrixSimulation

Acceptance: 64.3%

#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%

#2066Medium

Account Balance

Database

Acceptance: 82.1%

#2067Medium

Number of Equal Count Substrings

CountingPrefix SumString

Acceptance: 45.1%

#2069Medium

Walking Robot Simulation II

DesignSimulation

Acceptance: 43.2%

#2070Medium

Most Beautiful Item for Each Query

ArrayBinary SearchSorting

Acceptance: 62.2%

#2074Medium

Reverse Nodes in Even Length Groups

Linked List

Acceptance: 65.0%

#2075Medium

Decode the Slanted Ciphertext

SimulationString

Acceptance: 67.3%

#2077Medium

Paths in Maze That Lead to Same Room

Graph

Acceptance: 56.7%

#2079Medium

Watering Plants

ArraySimulation

Acceptance: 79.9%

#2080Medium

Range Frequency Queries

ArrayBinary SearchDesign+2

Acceptance: 44.3%

#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%

#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%

#2090Medium

K Radius Subarray Averages

ArraySliding Window

Acceptance: 46.0%

#2091Medium

Removing Minimum and Maximum From Array

ArrayGreedy

Acceptance: 67.5%

#2093Medium

Minimum Cost to Reach City With Discounts

GraphHeap (Priority Queue)Shortest Path

Acceptance: 61.0%

#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%

#2098Medium

Subsequence of Size K With the Largest Even Sum

ArrayGreedySorting

Acceptance: 35.5%

#2100Medium

Find Good Days to Rob the Bank

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 52.1%

#2101Medium

Detonate the Maximum Bombs

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 50.0%

#2104Medium

Sum of Subarray Ranges

ArrayMonotonic StackStack

Acceptance: 61.6%

#2105Medium

Watering Plants II

ArraySimulationTwo Pointers

Acceptance: 48.8%

#2107Medium

Number of Unique Flavors After Sharing K Candies

ArrayHash TableSliding Window

Acceptance: 62.4%

#2109Medium

Adding Spaces to a String

ArraySimulationString+1

Acceptance: 71.8%

#2110Medium

Number of Smooth Descent Periods of a Stock

ArrayDynamic ProgrammingMath

Acceptance: 67.7%

#2112Medium

The Airport With the Most Traffic

Database

Acceptance: 70.6%

#2113Medium

Elements in Array After Removing and Replacing Elements

Array

Acceptance: 69.1%

#2115Medium

Find All Possible Recipes from Given Supplies

ArrayGraphHash Table+2

Acceptance: 56.8%

#2116Medium

Check if a Parentheses String Can Be Valid

GreedyStackString

Acceptance: 45.1%

#2120Medium

Execution of All Suffix Instructions Staying in a Grid

SimulationString

Acceptance: 82.4%

#2121Medium

Intervals Between Identical Elements

ArrayHash TablePrefix Sum

Acceptance: 47.8%

#2125Medium

Number of Laser Beams in a Bank

ArrayMathMatrix+1

Acceptance: 87.0%

#2126Medium

Destroying Asteroids

ArrayGreedySorting

Acceptance: 59.7%

#2128Medium

Remove All Ones With Row and Column Flips

ArrayBit ManipulationMath+1

Acceptance: 76.2%

#2130Medium

Maximum Twin Sum of a Linked List

Linked ListStackTwo Pointers

Acceptance: 83.2%

#2131Medium

Longest Palindrome by Concatenating Two Letter Words

ArrayCountingGreedy+2

Acceptance: 53.5%

#2134Medium

Minimum Swaps to Group All 1's Together II

ArraySliding Window

Acceptance: 65.5%

#2135Medium

Count Words Obtained After Adding a Letter

ArrayBit ManipulationHash Table+2

Acceptance: 44.0%

#2137Medium

Pour Water Between Buckets to Make Water Levels Equal

ArrayBinary Search

Acceptance: 68.4%

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