Solutions & Explanations

Browse 4,029+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,029 Solutions961 Easy2102 Medium966 Hard

Title	Difficulty	Acceptance	Topics	Solution
2224. Minimum Number of Operations to Convert Time	Easy	66.3%	Greedy String	Read
2229. Check if an Array Is Consecutive	Easy	61.6%	Array Hash Table+1	Read
2230. The Users That Are Eligible for Discount	Easy	50.2%	Database	Read
2231. Largest Number After Digit Swaps by Parity	Easy	65.7%	Heap (Priority Queue)Sorting	Read
2235. Add Two Integers	Easy	88.0%	Math	Read
2236. Root Equals Sum of Children	Easy	84.8%	Binary Tree Tree	Read
2239. Find Closest Number to Zero	Easy	47.8%	Array	Read
2243. Calculate Digit Sum of a String	Easy	67.7%	Simulation String	Read
2248. Intersection of Multiple Arrays	Easy	68.8%	Array Counting+2	Read
2255. Count Prefixes of a Given String	Easy	74.3%	Array String	Read
2259. Remove Digit From Number to Maximize Result	Easy	48.4%	Enumeration Greedy+1	Read
2264. Largest 3-Same-Digit Number in String	Easy	72.7%	String	Read
2269. Find the K-Beauty of a Number	Easy	63.8%	Math Sliding Window+1	Read
2273. Find Resultant Array After Removing Anagrams	Easy	69.9%	Array Hash Table+2	Read
2278. Percentage of Letter in String	Easy	75.1%	String	Read
2283. Check if Number Has Equal Digit Count and Digit Value	Easy	73.1%	Counting Hash Table+1	Read
2287. Rearrange Characters to Make Target String	Easy	63.0%	Counting Hash Table+1	Read
2293. Min Max Game	Easy	64.3%	Array Simulation	Read
2299. Strong Password Checker II	Easy	55.5%	String	Read
2303. Calculate Amount Paid in Taxes	Easy	69.1%	Array Simulation	Read
2309. Greatest English Letter in Upper and Lower Case	Easy	72.6%	Enumeration Hash Table+1	Read
2315. Count Asterisks	Easy	83.3%	String	Read
2319. Check if Matrix Is X-Matrix	Easy	67.2%	Array Matrix	Read
2325. Decode the Message	Easy	85.8%	Hash Table String	Read
2329. Product Sales Analysis V	Easy	69.9%	Database	Read
2331. Evaluate Boolean Binary Tree	Easy	82.7%	Binary Tree Depth-First Search+1	Read
2335. Minimum Amount of Time to Fill Cups	Easy	60.1%	Array Greedy+2	Read
2339. All the Matches of the League	Easy	88.0%	Database	Read
2341. Maximum Number of Pairs in Array	Easy	76.0%	Array Counting+1	Read
2347. Best Poker Hand	Easy	61.7%	Array Counting+1	Read
2351. First Letter to Appear Twice	Easy	74.9%	Bit Manipulation Counting+2	Read
2356. Number of Unique Subjects Taught by Each Teacher	Easy	89.1%	Database	Read
2357. Make Array Zero by Subtracting Equal Amounts	Easy	73.8%	Array Greedy+4	Read
2363. Merge Similar Items	Easy	77.4%	Array Hash Table+2	Read
2367. Number of Arithmetic Triplets	Easy	85.4%	Array Enumeration+2	Read
2373. Largest Local Values in a Matrix	Easy	87.8%	Array Matrix	Read
2377. Sort the Olympic Table	Easy	79.1%	Database	Read
2379. Minimum Recolors to Get K Consecutive Black Blocks	Easy	68.6%	Sliding Window String	Read
2383. Minimum Hours of Training to Win a Competition	Easy	42.5%	Array Greedy	Read
2389. Longest Subsequence With Limited Sum	Easy	73.5%	Array Binary Search+3	Read
2395. Find Subarrays With Equal Sum	Easy	66.9%	Array Hash Table	Read
2399. Check Distances Between Same Letters	Easy	71.5%	Array Hash Table+1	Read
2404. Most Frequent Even Element	Easy	54.0%	Array Counting+1	Read
2409. Count Days Spent Together	Easy	48.3%	Math String	Read
2413. Smallest Even Multiple	Easy	88.5%	Math Number Theory	Read
2418. Sort the People	Easy	84.9%	Array Hash Table+2	Read
2423. Remove Letter To Equalize Frequency	Easy	19.3%	Counting Hash Table+1	Read
2427. Number of Common Factors	Easy	80.0%	Enumeration Math+1	Read
2432. The Employee That Worked on the Longest Task	Easy	51.5%	Array	Read
2437. Number of Valid Clock Times	Easy	47.9%	Enumeration String	Read

#2224Easy

Minimum Number of Operations to Convert Time

GreedyString

Acceptance: 66.3%

#2229Easy

Check if an Array Is Consecutive

ArrayHash TableSorting

Acceptance: 61.6%

#2230Easy

The Users That Are Eligible for Discount

Database

Acceptance: 50.2%

#2231Easy

Largest Number After Digit Swaps by Parity

Heap (Priority Queue)Sorting

Acceptance: 65.7%

#2235Easy

Add Two Integers

Math

Acceptance: 88.0%

#2236Easy

Root Equals Sum of Children

Binary TreeTree

Acceptance: 84.8%

#2239Easy

Find Closest Number to Zero

Array

Acceptance: 47.8%

#2243Easy

Calculate Digit Sum of a String

SimulationString

Acceptance: 67.7%

#2248Easy

Intersection of Multiple Arrays

ArrayCountingHash Table+1

Acceptance: 68.8%

#2255Easy

Count Prefixes of a Given String

ArrayString

Acceptance: 74.3%

#2259Easy

Remove Digit From Number to Maximize Result

EnumerationGreedyString

Acceptance: 48.4%

#2264Easy

Largest 3-Same-Digit Number in String

String

Acceptance: 72.7%

#2269Easy

Find the K-Beauty of a Number

MathSliding WindowString

Acceptance: 63.8%

#2273Easy

Find Resultant Array After Removing Anagrams

ArrayHash TableSorting+1

Acceptance: 69.9%

#2278Easy

Percentage of Letter in String

String

Acceptance: 75.1%

#2283Easy

Check if Number Has Equal Digit Count and Digit Value

CountingHash TableString

Acceptance: 73.1%

#2287Easy

Rearrange Characters to Make Target String

CountingHash TableString

Acceptance: 63.0%

#2293Easy

Min Max Game

ArraySimulation

Acceptance: 64.3%

#2299Easy

Strong Password Checker II

String

Acceptance: 55.5%

#2303Easy

Calculate Amount Paid in Taxes

ArraySimulation

Acceptance: 69.1%

#2309Easy

Greatest English Letter in Upper and Lower Case

EnumerationHash TableString

Acceptance: 72.6%

#2315Easy

Count Asterisks

String

Acceptance: 83.3%

#2319Easy

Check if Matrix Is X-Matrix

ArrayMatrix

Acceptance: 67.2%

#2325Easy

Decode the Message

Hash TableString

Acceptance: 85.8%

#2329Easy

Product Sales Analysis V

Database

Acceptance: 69.9%

#2331Easy

Evaluate Boolean Binary Tree

Binary TreeDepth-First SearchTree

Acceptance: 82.7%

#2335Easy

Minimum Amount of Time to Fill Cups

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 60.1%

#2339Easy

All the Matches of the League

Database

Acceptance: 88.0%

#2341Easy

Maximum Number of Pairs in Array

ArrayCountingHash Table

Acceptance: 76.0%

#2347Easy

Best Poker Hand

ArrayCountingHash Table

Acceptance: 61.7%

#2351Easy

First Letter to Appear Twice

Bit ManipulationCountingHash Table+1

Acceptance: 74.9%

#2356Easy

Number of Unique Subjects Taught by Each Teacher

Database

Acceptance: 89.1%

#2357Easy

Make Array Zero by Subtracting Equal Amounts

ArrayGreedyHash Table+3

Acceptance: 73.8%

#2363Easy

Merge Similar Items

ArrayHash TableOrdered Set+1

Acceptance: 77.4%

#2367Easy

Number of Arithmetic Triplets

ArrayEnumerationHash Table+1

Acceptance: 85.4%

#2373Easy

Largest Local Values in a Matrix

ArrayMatrix

Acceptance: 87.8%

#2377Easy

Sort the Olympic Table

Database

Acceptance: 79.1%

#2379Easy

Minimum Recolors to Get K Consecutive Black Blocks

Sliding WindowString

Acceptance: 68.6%

#2383Easy

Minimum Hours of Training to Win a Competition

ArrayGreedy

Acceptance: 42.5%

#2389Easy

Longest Subsequence With Limited Sum

ArrayBinary SearchGreedy+2

Acceptance: 73.5%

#2395Easy

Find Subarrays With Equal Sum

ArrayHash Table

Acceptance: 66.9%

#2399Easy

Check Distances Between Same Letters

ArrayHash TableString

Acceptance: 71.5%

#2404Easy

Most Frequent Even Element

ArrayCountingHash Table

Acceptance: 54.0%

#2409Easy

Count Days Spent Together

MathString

Acceptance: 48.3%

#2413Easy

Smallest Even Multiple

MathNumber Theory

Acceptance: 88.5%

#2418Easy

Sort the People

ArrayHash TableSorting+1

Acceptance: 84.9%

#2423Easy

Remove Letter To Equalize Frequency

CountingHash TableString

Acceptance: 19.3%

#2427Easy

Number of Common Factors

EnumerationMathNumber Theory

Acceptance: 80.0%

#2432Easy

The Employee That Worked on the Longest Task

Array

Acceptance: 51.5%

#2437Easy

Number of Valid Clock Times

EnumerationString

Acceptance: 47.9%

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Master DSA with Step-by-Step Solutions

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