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
2201. Count Artifacts That Can Be Extracted	Medium	57.1%	Array Hash Table+1	Read
2202. Maximize the Topmost Element After K Moves	Medium	24.0%	Array Greedy	Read
2203. Minimum Weighted Subgraph With the Required Paths	Hard	43.2%	Graph Shortest Path	Read
2204. Distance to a Cycle in Undirected Graph	Hard	73.4%	Breadth-First Search Depth-First Search+2	Read
2205. The Number of Users That Are Eligible for Discount	Easy	50.3%	Database	Read
2206. Divide Array Into Equal Pairs	Easy	79.2%	Array Bit Manipulation+2	Read
2207. Maximize Number of Subsequences in a String	Medium	36.0%	Greedy Prefix Sum+1	Read
2208. Minimum Operations to Halve Array Sum	Medium	50.1%	Array Greedy+1	Read
2209. Minimum White Tiles After Covering With Carpets	Hard	39.3%	Dynamic Programming Prefix Sum+1	Read
2210. Count Hills and Valleys in an Array	Easy	69.1%	Array	Read
2211. Count Collisions on a Road	Medium	58.1%	Simulation Stack+1	Read
2212. Maximum Points in an Archery Competition	Medium	52.2%	Array Backtracking+2	Read
2213. Longest Substring of One Repeating Character	Hard	65.8%	Array Ordered Set+2	Read
2214. Minimum Health to Beat Game	Medium	58.9%	Array Greedy	Read
2215. Find the Difference of Two Arrays	Easy	81.4%	Array Hash Table	Read
2216. Minimum Deletions to Make Array Beautiful	Medium	50.5%	Array Greedy+1	Read
2217. Find Palindrome With Fixed Length	Medium	38.0%	Array Math	Read
2218. Maximum Value of K Coins From Piles	Hard	60.5%	Array Dynamic Programming+1	Read
2219. Maximum Sum Score of Array	Medium	62.6%	Array Prefix Sum	Read
2220. Minimum Bit Flips to Convert Number	Easy	88.0%	Bit Manipulation	Read
2221. Find Triangular Sum of an Array	Medium	82.0%	Array Combinatorics+2	Read
2222. Number of Ways to Select Buildings	Medium	50.8%	Dynamic Programming Prefix Sum+1	Read
2223. Sum of Scores of Built Strings	Hard	50.4%	Binary Search Hash Function+4	Read
2224. Minimum Number of Operations to Convert Time	Easy	66.3%	Greedy String	Read
2225. Find Players With Zero or One Losses	Medium	72.4%	Array Counting+2	Read
2226. Maximum Candies Allocated to K Children	Medium	49.9%	Array Binary Search	Read
2227. Encrypt and Decrypt Strings	Hard	38.8%	Array Design+3	Read
2228. Users With Two Purchases Within Seven Days	Medium	45.2%	Database	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
2232. Minimize Result by Adding Parentheses to Expression	Medium	68.4%	Enumeration String	Read
2233. Maximum Product After K Increments	Medium	44.0%	Array Greedy+1	Read
2234. Maximum Total Beauty of the Gardens	Hard	30.4%	Array Binary Search+3	Read
2235. Add Two Integers	Easy	88.0%	Math	Read
2236. Root Equals Sum of Children	Easy	84.8%	Binary Tree Tree	Read
2237. Count Positions on Street With Required Brightness	Medium	62.4%	Array Prefix Sum	Read
2238. Number of Times a Driver Was a Passenger	Medium	71.5%	Database	Read
2239. Find Closest Number to Zero	Easy	47.8%	Array	Read
2240. Number of Ways to Buy Pens and Pencils	Medium	57.2%	Enumeration Math	Read
2241. Design an ATM Machine	Medium	46.0%	Array Design+1	Read
2242. Maximum Score of a Node Sequence	Hard	40.5%	Array Enumeration+2	Read
2243. Calculate Digit Sum of a String	Easy	67.7%	Simulation String	Read
2244. Minimum Rounds to Complete All Tasks	Medium	62.9%	Array Counting+2	Read
2245. Maximum Trailing Zeros in a Cornered Path	Medium	38.2%	Array Matrix+1	Read
2246. Longest Path With Different Adjacent Characters	Hard	54.2%	Array Depth-First Search+4	Read
2247. Maximum Cost of Trip With K Highways	Hard	50.2%	Bit Manipulation Bitmask+2	Read
2248. Intersection of Multiple Arrays	Easy	68.8%	Array Counting+2	Read
2249. Count Lattice Points Inside a Circle	Medium	57.1%	Array Enumeration+3	Read
2250. Count Number of Rectangles Containing Each Point	Medium	37.5%	Array Binary Indexed Tree+2	Read

#2201Medium

Count Artifacts That Can Be Extracted

ArrayHash TableSimulation

Acceptance: 57.1%

#2202Medium

Maximize the Topmost Element After K Moves

ArrayGreedy

Acceptance: 24.0%

#2203Hard

Minimum Weighted Subgraph With the Required Paths

GraphShortest Path

Acceptance: 43.2%

#2204Hard

Distance to a Cycle in Undirected Graph

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 73.4%

#2205Easy

The Number of Users That Are Eligible for Discount

Database

Acceptance: 50.3%

#2206Easy

Divide Array Into Equal Pairs

ArrayBit ManipulationCounting+1

Acceptance: 79.2%

#2207Medium

Maximize Number of Subsequences in a String

GreedyPrefix SumString

Acceptance: 36.0%

#2208Medium

Minimum Operations to Halve Array Sum

ArrayGreedyHeap (Priority Queue)

Acceptance: 50.1%

#2209Hard

Minimum White Tiles After Covering With Carpets

Dynamic ProgrammingPrefix SumString

Acceptance: 39.3%

#2210Easy

Count Hills and Valleys in an Array

Array

Acceptance: 69.1%

#2211Medium

Count Collisions on a Road

SimulationStackString

Acceptance: 58.1%

#2212Medium

Maximum Points in an Archery Competition

ArrayBacktrackingBit Manipulation+1

Acceptance: 52.2%

#2213Hard

Longest Substring of One Repeating Character

ArrayOrdered SetSegment Tree+1

Acceptance: 65.8%

#2214Medium

Minimum Health to Beat Game

ArrayGreedy

Acceptance: 58.9%

#2215Easy

Find the Difference of Two Arrays

ArrayHash Table

Acceptance: 81.4%

#2216Medium

Minimum Deletions to Make Array Beautiful

ArrayGreedyStack

Acceptance: 50.5%

#2217Medium

Find Palindrome With Fixed Length

ArrayMath

Acceptance: 38.0%

#2218Hard

Maximum Value of K Coins From Piles

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 60.5%

#2219Medium

Maximum Sum Score of Array

ArrayPrefix Sum

Acceptance: 62.6%

#2220Easy

Minimum Bit Flips to Convert Number

Bit Manipulation

Acceptance: 88.0%

#2221Medium

Find Triangular Sum of an Array

ArrayCombinatoricsMath+1

Acceptance: 82.0%

#2222Medium

Number of Ways to Select Buildings

Dynamic ProgrammingPrefix SumString

Acceptance: 50.8%

#2223Hard

Sum of Scores of Built Strings

Binary SearchHash FunctionRolling Hash+3

Acceptance: 50.4%

#2224Easy

Minimum Number of Operations to Convert Time

GreedyString

Acceptance: 66.3%

#2225Medium

Find Players With Zero or One Losses

ArrayCountingHash Table+1

Acceptance: 72.4%

#2226Medium

Maximum Candies Allocated to K Children

ArrayBinary Search

Acceptance: 49.9%

#2227Hard

Encrypt and Decrypt Strings

ArrayDesignHash Table+2

Acceptance: 38.8%

#2228Medium

Users With Two Purchases Within Seven Days

Database

Acceptance: 45.2%

#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%

#2232Medium

Minimize Result by Adding Parentheses to Expression

EnumerationString

Acceptance: 68.4%

#2233Medium

Maximum Product After K Increments

ArrayGreedyHeap (Priority Queue)

Acceptance: 44.0%

#2234Hard

Maximum Total Beauty of the Gardens

ArrayBinary SearchGreedy+2

Acceptance: 30.4%

#2235Easy

Add Two Integers

Math

Acceptance: 88.0%

#2236Easy

Root Equals Sum of Children

Binary TreeTree

Acceptance: 84.8%

#2237Medium

Count Positions on Street With Required Brightness

ArrayPrefix Sum

Acceptance: 62.4%

#2238Medium

Number of Times a Driver Was a Passenger

Database

Acceptance: 71.5%

#2239Easy

Find Closest Number to Zero

Array

Acceptance: 47.8%

#2240Medium

Number of Ways to Buy Pens and Pencils

EnumerationMath

Acceptance: 57.2%

#2241Medium

Design an ATM Machine

ArrayDesignGreedy

Acceptance: 46.0%

#2242Hard

Maximum Score of a Node Sequence

ArrayEnumerationGraph+1

Acceptance: 40.5%

#2243Easy

Calculate Digit Sum of a String

SimulationString

Acceptance: 67.7%

#2244Medium

Minimum Rounds to Complete All Tasks

ArrayCountingGreedy+1

Acceptance: 62.9%

#2245Medium

Maximum Trailing Zeros in a Cornered Path

ArrayMatrixPrefix Sum

Acceptance: 38.2%

#2246Hard

Longest Path With Different Adjacent Characters

ArrayDepth-First SearchGraph+3

Acceptance: 54.2%

#2247Hard

Maximum Cost of Trip With K Highways

Bit ManipulationBitmaskDynamic Programming+1

Acceptance: 50.2%

#2248Easy

Intersection of Multiple Arrays

ArrayCountingHash Table+1

Acceptance: 68.8%

#2249Medium

Count Lattice Points Inside a Circle

ArrayEnumerationGeometry+2

Acceptance: 57.1%

#2250Medium

Count Number of Rectangles Containing Each Point

ArrayBinary Indexed TreeBinary Search+1

Acceptance: 37.5%

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