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
2301. Match Substring After Replacement	Hard	43.3%	Array Hash Table+2	Read
2302. Count Subarrays With Score Less Than K	Hard	62.3%	Array Binary Search+2	Read
2303. Calculate Amount Paid in Taxes	Easy	69.1%	Array Simulation	Read
2304. Minimum Path Cost in a Grid	Medium	68.0%	Array Dynamic Programming+1	Read
2305. Fair Distribution of Cookies	Medium	69.8%	Array Backtracking+3	Read
2306. Naming a Company	Hard	46.4%	Array Bit Manipulation+3	Read
2307. Check for Contradictions in Equations	Hard	43.8%	Array Depth-First Search+2	Read
2308. Arrange Table by Gender	Medium	69.5%	Database	Read
2309. Greatest English Letter in Upper and Lower Case	Easy	72.6%	Enumeration Hash Table+1	Read
2310. Sum of Numbers With Units Digit K	Medium	28.2%	Dynamic Programming Enumeration+2	Read
2311. Longest Binary Subsequence Less Than or Equal to K	Medium	52.8%	Dynamic Programming Greedy+2	Read
2312. Selling Pieces of Wood	Hard	52.8%	Array Dynamic Programming+1	Read
2313. Minimum Flips in Binary Tree to Get Result	Hard	56.9%	Binary Tree Depth-First Search+2	Read
2314. The First Day of the Maximum Recorded Degree in Each City	Medium	72.2%	Database	Read
2315. Count Asterisks	Easy	83.3%	String	Read
2316. Count Unreachable Pairs of Nodes in an Undirected Graph	Medium	49.9%	Breadth-First Search Depth-First Search+2	Read
2317. Maximum XOR After Operations	Medium	79.9%	Array Bit Manipulation+1	Read
2318. Number of Distinct Roll Sequences	Hard	58.2%	Dynamic Programming Memoization	Read
2319. Check if Matrix Is X-Matrix	Easy	67.2%	Array Matrix	Read
2320. Count Number of Ways to Place Houses	Medium	43.8%	Dynamic Programming	Read
2321. Maximum Score Of Spliced Array	Hard	58.9%	Array Dynamic Programming	Read
2322. Minimum Score After Removals on a Tree	Hard	76.2%	Array Bit Manipulation+2	Read
2323. Find Minimum Time to Finish All Jobs II	Medium	65.8%	Array Greedy+1	Read
2324. Product Sales Analysis IV	Medium	74.7%	Database	Read
2325. Decode the Message	Easy	85.8%	Hash Table String	Read
2326. Spiral Matrix IV	Medium	82.3%	Array Linked List+2	Read
2327. Number of People Aware of a Secret	Medium	60.9%	Dynamic Programming Queue+1	Read
2328. Number of Increasing Paths in a Grid	Hard	57.4%	Array Breadth-First Search+6	Read
2329. Product Sales Analysis V	Easy	69.9%	Database	Read
2330. Valid Palindrome IV	Medium	75.8%	String Two Pointers	Read
2331. Evaluate Boolean Binary Tree	Easy	82.7%	Binary Tree Depth-First Search+1	Read
2332. The Latest Time to Catch a Bus	Medium	30.0%	Array Binary Search+2	Read
2333. Minimum Sum of Squared Difference	Medium	26.8%	Array Binary Search+3	Read
2334. Subarray With Elements Greater Than Varying Threshold	Hard	45.9%	Array Monotonic Stack+2	Read
2335. Minimum Amount of Time to Fill Cups	Easy	60.1%	Array Greedy+2	Read
2336. Smallest Number in Infinite Set	Medium	70.6%	Design Hash Table+2	Read
2337. Move Pieces to Obtain a String	Medium	56.7%	String Two Pointers	Read
2338. Count the Number of Ideal Arrays	Hard	57.0%	Combinatorics Dynamic Programming+2	Read
2339. All the Matches of the League	Easy	88.0%	Database	Read
2340. Minimum Adjacent Swaps to Make a Valid Array	Medium	72.6%	Array Greedy	Read
2341. Maximum Number of Pairs in Array	Easy	76.0%	Array Counting+1	Read
2342. Max Sum of a Pair With Equal Sum of Digits	Medium	66.0%	Array Hash Table+2	Read
2343. Query Kth Smallest Trimmed Number	Medium	47.9%	Array Divide and Conquer+5	Read
2344. Minimum Deletions to Make Array Divisible	Hard	61.8%	Array Heap (Priority Queue)+3	Read
2345. Finding the Number of Visible Mountains	Medium	37.3%	Array Monotonic Stack+2	Read
2346. Compute the Rank as a Percentage	Medium	33.7%	Database	Read
2347. Best Poker Hand	Easy	61.7%	Array Counting+1	Read
2348. Number of Zero-Filled Subarrays	Medium	70.1%	Array Math	Read
2349. Design a Number Container System	Medium	57.1%	Design Hash Table+2	Read
2350. Shortest Impossible Sequence of Rolls	Hard	69.3%	Array Greedy+1	Read

#2301Hard

Match Substring After Replacement

ArrayHash TableString+1

Acceptance: 43.3%

#2302Hard

Count Subarrays With Score Less Than K

ArrayBinary SearchPrefix Sum+1

Acceptance: 62.3%

#2303Easy

Calculate Amount Paid in Taxes

ArraySimulation

Acceptance: 69.1%

#2304Medium

Minimum Path Cost in a Grid

ArrayDynamic ProgrammingMatrix

Acceptance: 68.0%

#2305Medium

Fair Distribution of Cookies

ArrayBacktrackingBit Manipulation+2

Acceptance: 69.8%

#2306Hard

Naming a Company

ArrayBit ManipulationEnumeration+2

Acceptance: 46.4%

#2307Hard

Check for Contradictions in Equations

ArrayDepth-First SearchGraph+1

Acceptance: 43.8%

#2308Medium

Arrange Table by Gender

Database

Acceptance: 69.5%

#2309Easy

Greatest English Letter in Upper and Lower Case

EnumerationHash TableString

Acceptance: 72.6%

#2310Medium

Sum of Numbers With Units Digit K

Dynamic ProgrammingEnumerationGreedy+1

Acceptance: 28.2%

#2311Medium

Longest Binary Subsequence Less Than or Equal to K

Dynamic ProgrammingGreedyMemoization+1

Acceptance: 52.8%

#2312Hard

Selling Pieces of Wood

ArrayDynamic ProgrammingMemoization

Acceptance: 52.8%

#2313Hard

Minimum Flips in Binary Tree to Get Result

Binary TreeDepth-First SearchDynamic Programming+1

Acceptance: 56.9%

#2314Medium

The First Day of the Maximum Recorded Degree in Each City

Database

Acceptance: 72.2%

#2315Easy

Count Asterisks

String

Acceptance: 83.3%

#2316Medium

Count Unreachable Pairs of Nodes in an Undirected Graph

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 49.9%

#2317Medium

Maximum XOR After Operations

ArrayBit ManipulationMath

Acceptance: 79.9%

#2318Hard

Number of Distinct Roll Sequences

Dynamic ProgrammingMemoization

Acceptance: 58.2%

#2319Easy

Check if Matrix Is X-Matrix

ArrayMatrix

Acceptance: 67.2%

#2320Medium

Count Number of Ways to Place Houses

Dynamic Programming

Acceptance: 43.8%

#2321Hard

Maximum Score Of Spliced Array

ArrayDynamic Programming

Acceptance: 58.9%

#2322Hard

Minimum Score After Removals on a Tree

ArrayBit ManipulationDepth-First Search+1

Acceptance: 76.2%

#2323Medium

Find Minimum Time to Finish All Jobs II

ArrayGreedySorting

Acceptance: 65.8%

#2324Medium

Product Sales Analysis IV

Database

Acceptance: 74.7%

#2325Easy

Decode the Message

Hash TableString

Acceptance: 85.8%

#2326Medium

Spiral Matrix IV

ArrayLinked ListMatrix+1

Acceptance: 82.3%

#2327Medium

Number of People Aware of a Secret

Dynamic ProgrammingQueueSimulation

Acceptance: 60.9%

#2328Hard

Number of Increasing Paths in a Grid

ArrayBreadth-First SearchDepth-First Search+5

Acceptance: 57.4%

#2329Easy

Product Sales Analysis V

Database

Acceptance: 69.9%

#2330Medium

Valid Palindrome IV

StringTwo Pointers

Acceptance: 75.8%

#2331Easy

Evaluate Boolean Binary Tree

Binary TreeDepth-First SearchTree

Acceptance: 82.7%

#2332Medium

The Latest Time to Catch a Bus

ArrayBinary SearchSorting+1

Acceptance: 30.0%

#2333Medium

Minimum Sum of Squared Difference

ArrayBinary SearchGreedy+2

Acceptance: 26.8%

#2334Hard

Subarray With Elements Greater Than Varying Threshold

ArrayMonotonic StackStack+1

Acceptance: 45.9%

#2335Easy

Minimum Amount of Time to Fill Cups

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 60.1%

#2336Medium

Smallest Number in Infinite Set

DesignHash TableHeap (Priority Queue)+1

Acceptance: 70.6%

#2337Medium

Move Pieces to Obtain a String

StringTwo Pointers

Acceptance: 56.7%

#2338Hard

Count the Number of Ideal Arrays

CombinatoricsDynamic ProgrammingMath+1

Acceptance: 57.0%

#2339Easy

All the Matches of the League

Database

Acceptance: 88.0%

#2340Medium

Minimum Adjacent Swaps to Make a Valid Array

ArrayGreedy

Acceptance: 72.6%

#2341Easy

Maximum Number of Pairs in Array

ArrayCountingHash Table

Acceptance: 76.0%

#2342Medium

Max Sum of a Pair With Equal Sum of Digits

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 66.0%

#2343Medium

Query Kth Smallest Trimmed Number

ArrayDivide and ConquerHeap (Priority Queue)+4

Acceptance: 47.9%

#2344Hard

Minimum Deletions to Make Array Divisible

ArrayHeap (Priority Queue)Math+2

Acceptance: 61.8%

#2345Medium

Finding the Number of Visible Mountains

ArrayMonotonic StackSorting+1

Acceptance: 37.3%

#2346Medium

Compute the Rank as a Percentage

Database

Acceptance: 33.7%

#2347Easy

Best Poker Hand

ArrayCountingHash Table

Acceptance: 61.7%

#2348Medium

Number of Zero-Filled Subarrays

ArrayMath

Acceptance: 70.1%

#2349Medium

Design a Number Container System

DesignHash TableHeap (Priority Queue)+1

Acceptance: 57.1%

#2350Hard

Shortest Impossible Sequence of Rolls

ArrayGreedyHash Table

Acceptance: 69.3%

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