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
2101. Detonate the Maximum Bombs	Medium	50.0%	Array Breadth-First Search+4	Read
2102. Sequentially Ordinal Rank Tracker	Hard	61.5%	Data Stream Design+2	Read
2103. Rings and Rods	Easy	81.5%	Hash Table String	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
2106. Maximum Fruits Harvested After at Most K Steps	Hard	61.0%	Array Binary Search+2	Read
2107. Number of Unique Flavors After Sharing K Candies	Medium	62.4%	Array Hash Table+1	Read
2108. Find First Palindromic String in the Array	Easy	83.9%	Array String+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
2111. Minimum Operations to Make the Array K-Increasing	Hard	40.5%	Array Binary Search	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
2114. Maximum Number of Words Found in Sentences	Easy	86.6%	Array String	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
2117. Abbreviating the Product of a Range	Hard	25.0%	Math	Read
2118. Build the Equation	Hard	55.9%	Database	Read
2119. A Number After a Double Reversal	Easy	82.7%	Math	Read
2120. Execution of All Suffix Instructions Staying in a Grid	Medium	82.4%	Simulation String	Read
2121. Intervals Between Identical Elements	Medium	48.4%	Array Hash Table+1	Read
2122. Recover the Original Array	Hard	42.0%	Array Enumeration+3	Read
2123. Minimum Operations to Remove Adjacent Ones in Matrix	Hard	42.5%	Array Graph+1	Read
2124. Check if All A's Appears Before All B's	Easy	73.2%	String	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
2127. Maximum Employees to Be Invited to a Meeting	Hard	61.8%	Depth-First Search Graph+1	Read
2128. Remove All Ones With Row and Column Flips	Medium	76.2%	Array Bit Manipulation+2	Read
2129. Capitalize the Title	Easy	68.5%	String	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
2132. Stamping the Grid	Hard	35.7%	Array Greedy+2	Read
2133. Check if Every Row and Column Contains All Numbers	Easy	54.0%	Array Hash Table+1	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
2136. Earliest Possible Day of Full Bloom	Hard	71.4%	Array Greedy+1	Read
2137. Pour Water Between Buckets to Make Water Levels Equal	Medium	68.4%	Array Binary Search	Read
2138. Divide a String Into Groups of Size k	Easy	77.1%	Simulation String	Read
2139. Minimum Moves to Reach Target Score	Medium	52.3%	Greedy Math	Read
2140. Solving Questions With Brainpower	Medium	60.2%	Array Dynamic Programming	Read
2141. Maximum Running Time of N Computers	Hard	56.4%	Array Binary Search+2	Read
2142. The Number of Passengers in Each Bus I	Medium	48.8%	Database	Read
2143. Choose Numbers From Two Arrays in Range	Hard	51.4%	Array Dynamic Programming	Read
2144. Minimum Cost of Buying Candies With Discount	Easy	71.5%	Array Greedy+1	Read
2145. Count the Hidden Sequences	Medium	56.7%	Array Prefix Sum	Read
2146. K Highest Ranked Items Within a Price Range	Medium	47.1%	Array Breadth-First Search+3	Read
2147. Number of Ways to Divide a Long Corridor	Hard	54.6%	Dynamic Programming Math+1	Read
2148. Count Elements With Strictly Smaller and Greater Elements	Easy	59.9%	Array Counting+1	Read
2149. Rearrange Array Elements by Sign	Medium	84.7%	Array Simulation+1	Read
2150. Find All Lonely Numbers in the Array	Medium	63.4%	Array Counting+1	Read

#2101Medium

Detonate the Maximum Bombs

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 50.0%

#2102Hard

Sequentially Ordinal Rank Tracker

Data StreamDesignHeap (Priority Queue)+1

Acceptance: 61.5%

#2103Easy

Rings and Rods

Hash TableString

Acceptance: 81.5%

#2104Medium

Sum of Subarray Ranges

ArrayMonotonic StackStack

Acceptance: 61.6%

#2105Medium

Watering Plants II

ArraySimulationTwo Pointers

Acceptance: 48.8%

#2106Hard

Maximum Fruits Harvested After at Most K Steps

ArrayBinary SearchPrefix Sum+1

Acceptance: 61.0%

#2107Medium

Number of Unique Flavors After Sharing K Candies

ArrayHash TableSliding Window

Acceptance: 62.4%

#2108Easy

Find First Palindromic String in the Array

ArrayStringTwo Pointers

Acceptance: 83.9%

#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%

#2111Hard

Minimum Operations to Make the Array K-Increasing

ArrayBinary Search

Acceptance: 40.5%

#2112Medium

The Airport With the Most Traffic

Database

Acceptance: 70.6%

#2113Medium

Elements in Array After Removing and Replacing Elements

Array

Acceptance: 69.1%

#2114Easy

Maximum Number of Words Found in Sentences

ArrayString

Acceptance: 86.6%

#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%

#2117Hard

Abbreviating the Product of a Range

Math

Acceptance: 25.0%

#2118Hard

Build the Equation

Database

Acceptance: 55.9%

#2119Easy

A Number After a Double Reversal

Math

Acceptance: 82.7%

#2120Medium

Execution of All Suffix Instructions Staying in a Grid

SimulationString

Acceptance: 82.4%

#2121Medium

Intervals Between Identical Elements

ArrayHash TablePrefix Sum

Acceptance: 48.4%

#2122Hard

Recover the Original Array

ArrayEnumerationHash Table+2

Acceptance: 42.0%

#2123Hard

Minimum Operations to Remove Adjacent Ones in Matrix

ArrayGraphMatrix

Acceptance: 42.5%

#2124Easy

Check if All A's Appears Before All B's

String

Acceptance: 73.2%

#2125Medium

Number of Laser Beams in a Bank

ArrayMathMatrix+1

Acceptance: 87.0%

#2126Medium

Destroying Asteroids

ArrayGreedySorting

Acceptance: 59.7%

#2127Hard

Maximum Employees to Be Invited to a Meeting

Depth-First SearchGraphTopological Sort

Acceptance: 61.8%

#2128Medium

Remove All Ones With Row and Column Flips

ArrayBit ManipulationMath+1

Acceptance: 76.2%

#2129Easy

Capitalize the Title

String

Acceptance: 68.5%

#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%

#2132Hard

Stamping the Grid

ArrayGreedyMatrix+1

Acceptance: 35.7%

#2133Easy

Check if Every Row and Column Contains All Numbers

ArrayHash TableMatrix

Acceptance: 54.0%

#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%

#2136Hard

Earliest Possible Day of Full Bloom

ArrayGreedySorting

Acceptance: 71.4%

#2137Medium

Pour Water Between Buckets to Make Water Levels Equal

ArrayBinary Search

Acceptance: 68.4%

#2138Easy

Divide a String Into Groups of Size k

SimulationString

Acceptance: 77.1%

#2139Medium

Minimum Moves to Reach Target Score

GreedyMath

Acceptance: 52.3%

#2140Medium

Solving Questions With Brainpower

ArrayDynamic Programming

Acceptance: 60.2%

#2141Hard

Maximum Running Time of N Computers

ArrayBinary SearchGreedy+1

Acceptance: 56.4%

#2142Medium

The Number of Passengers in Each Bus I

Database

Acceptance: 48.8%

#2143Hard

Choose Numbers From Two Arrays in Range

ArrayDynamic Programming

Acceptance: 51.4%

#2144Easy

Minimum Cost of Buying Candies With Discount

ArrayGreedySorting

Acceptance: 71.5%

#2145Medium

Count the Hidden Sequences

ArrayPrefix Sum

Acceptance: 56.7%

#2146Medium

K Highest Ranked Items Within a Price Range

ArrayBreadth-First SearchHeap (Priority Queue)+2

Acceptance: 47.1%

#2147Hard

Number of Ways to Divide a Long Corridor

Dynamic ProgrammingMathString

Acceptance: 54.6%

#2148Easy

Count Elements With Strictly Smaller and Greater Elements

ArrayCountingSorting

Acceptance: 59.9%

#2149Medium

Rearrange Array Elements by Sign

ArraySimulationTwo Pointers

Acceptance: 84.7%

#2150Medium

Find All Lonely Numbers in the Array

ArrayCountingHash Table

Acceptance: 63.4%

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Master DSA with Step-by-Step Solutions

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