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
3138. Minimum Length of Anagram Concatenation	Medium	39.8%	Counting Hash Table+1	Read
3140. Consecutive Available Seats II	Medium	58.6%	Database	Read
3143. Maximum Points Inside the Square	Medium	39.9%	Array Binary Search+3	Read
3144. Minimum Substring Partition of Equal Character Frequency	Medium	40.5%	Counting Dynamic Programming+2	Read
3147. Taking Maximum Energy From the Mystic Dungeon	Medium	61.0%	Array Prefix Sum	Read
3148. Maximum Difference Score in a Grid	Medium	48.4%	Array Dynamic Programming+1	Read
3152. Special Array II	Medium	45.8%	Array Binary Search+1	Read
3153. Sum of Digit Differences of All Pairs	Medium	43.3%	Array Counting+2	Read
3155. Maximum Number of Upgradable Servers	Medium	43.8%	Array Binary Search+1	Read
3157. Find the Level of Tree with Minimum Sum	Medium	69.6%	Binary Tree Breadth-First Search+2	Read
3159. Find Occurrences of an Element in an Array	Medium	73.6%	Array Hash Table	Read
3160. Find the Number of Distinct Colors Among the Balls	Medium	54.2%	Array Hash Table+1	Read
3163. String Compression III	Medium	67.0%	String	Read
3164. Find the Number of Good Pairs II	Medium	26.6%	Array Hash Table	Read
3166. Calculate Parking Fees and Duration	Medium	53.0%	Database	Read
3167. Better Compression of String	Medium	75.3%	Counting Hash Table+2	Read
3169. Count Days Without Meetings	Medium	48.1%	Array Sorting	Read
3170. Lexicographically Minimum String After Removing Stars	Medium	51.0%	Greedy Hash Table+3	Read
3175. Find The First Player to win K Games in a Row	Medium	40.1%	Array Simulation	Read
3176. Find the Maximum Length of a Good Subsequence I	Medium	32.6%	Array Dynamic Programming+1	Read
3179. Find the N-th Value After K Seconds	Medium	54.0%	Array Combinatorics+3	Read
3180. Maximum Total Reward Using Operations I	Medium	30.8%	Array Dynamic Programming	Read
3182. Find Top Scoring Students	Medium	49.4%	Database	Read
3183. The Number of Ways to Make the Sum	Medium	50.8%	Array Dynamic Programming	Read
3185. Count Pairs That Form a Complete Day II	Medium	43.7%	Array Counting+1	Read
3186. Maximum Total Damage With Spell Casting	Medium	45.1%	Array Binary Search+5	Read
3189. Minimum Moves to Get a Peaceful Board	Medium	75.9%	Array Counting Sort+2	Read
3191. Minimum Operations to Make Binary Array Elements Equal to One I	Medium	80.4%	Array Bit Manipulation+3	Read
3192. Minimum Operations to Make Binary Array Elements Equal to One II	Medium	65.1%	Array Dynamic Programming+1	Read
3195. Find the Minimum Area to Cover All Ones I	Medium	78.2%	Array Matrix	Read
3196. Maximize Total Cost of Alternating Subarrays	Medium	29.6%	Array Dynamic Programming	Read
3201. Find the Maximum Length of Valid Subsequence I	Medium	54.9%	Array Dynamic Programming	Read
3202. Find the Maximum Length of Valid Subsequence II	Medium	57.2%	Array Dynamic Programming	Read
3204. Bitwise User Permissions Analysis	Medium	94.3%	Database	Read
3205. Maximum Array Hopping Score I	Medium	77.0%	Array Dynamic Programming+3	Read
3207. Maximum Points After Enemy Battles	Medium	33.2%	Array Greedy	Read
3208. Alternating Groups II	Medium	59.9%	Array Sliding Window	Read
3211. Generate Binary Strings Without Adjacent Zeros	Medium	88.3%	Backtracking Bit Manipulation+1	Read
3212. Count Submatrices With Equal Frequency of X and Y	Medium	69.5%	Array Matrix+1	Read
3215. Count Triplets with Even XOR Set Bits II	Medium	62.0%	Array Bit Manipulation	Read
3217. Delete Nodes From Linked List Present in Array	Medium	69.5%	Array Hash Table+1	Read
3218. Minimum Cost for Cutting Cake I	Medium	58.5%	Array Dynamic Programming+2	Read
3220. Odd and Even Transactions	Medium	69.8%	Database	Read
3221. Maximum Array Hopping Score II	Medium	60.1%	Array Greedy+2	Read
3223. Minimum Length of String After Operations	Medium	75.0%	Counting Hash Table+1	Read
3224. Minimum Array Changes to Make Differences Equal	Medium	24.9%	Array Hash Table+1	Read
3227. Vowels Game in a String	Medium	77.1%	Brainteaser Game Theory+2	Read
3228. Maximum Number of Operations to Move Ones to the End	Medium	67.2%	Counting Greedy+1	Read
3230. Customer Purchasing Behavior Analysis	Medium	37.8%	Database	Read
3233. Find the Count of Numbers Which Are Not Special	Medium	28.3%	Array Math+1	Read

#3138Medium

Minimum Length of Anagram Concatenation

CountingHash TableString

Acceptance: 39.8%

#3140Medium

Consecutive Available Seats II

Database

Acceptance: 58.6%

#3143Medium

Maximum Points Inside the Square

ArrayBinary SearchHash Table+2

Acceptance: 39.9%

#3144Medium

Minimum Substring Partition of Equal Character Frequency

CountingDynamic ProgrammingHash Table+1

Acceptance: 40.5%

#3147Medium

Taking Maximum Energy From the Mystic Dungeon

ArrayPrefix Sum

Acceptance: 61.0%

#3148Medium

Maximum Difference Score in a Grid

ArrayDynamic ProgrammingMatrix

Acceptance: 48.4%

#3152Medium

Special Array II

ArrayBinary SearchPrefix Sum

Acceptance: 45.8%

#3153Medium

Sum of Digit Differences of All Pairs

ArrayCountingHash Table+1

Acceptance: 43.3%

#3155Medium

Maximum Number of Upgradable Servers

ArrayBinary SearchMath

Acceptance: 43.8%

#3157Medium

Find the Level of Tree with Minimum Sum

Binary TreeBreadth-First SearchDepth-First Search+1

Acceptance: 69.6%

#3159Medium

Find Occurrences of an Element in an Array

ArrayHash Table

Acceptance: 73.6%

#3160Medium

Find the Number of Distinct Colors Among the Balls

ArrayHash TableSimulation

Acceptance: 54.2%

#3163Medium

String Compression III

String

Acceptance: 67.0%

#3164Medium

Find the Number of Good Pairs II

ArrayHash Table

Acceptance: 26.6%

#3166Medium

Calculate Parking Fees and Duration

Database

Acceptance: 53.0%

#3167Medium

Better Compression of String

CountingHash TableSorting+1

Acceptance: 75.3%

#3169Medium

Count Days Without Meetings

ArraySorting

Acceptance: 48.1%

#3170Medium

Lexicographically Minimum String After Removing Stars

GreedyHash TableHeap (Priority Queue)+2

Acceptance: 51.0%

#3175Medium

Find The First Player to win K Games in a Row

ArraySimulation

Acceptance: 40.1%

#3176Medium

Find the Maximum Length of a Good Subsequence I

ArrayDynamic ProgrammingHash Table

Acceptance: 32.6%

#3179Medium

Find the N-th Value After K Seconds

ArrayCombinatoricsMath+2

Acceptance: 54.0%

#3180Medium

Maximum Total Reward Using Operations I

ArrayDynamic Programming

Acceptance: 30.8%

#3182Medium

Find Top Scoring Students

Database

Acceptance: 49.4%

#3183Medium

The Number of Ways to Make the Sum

ArrayDynamic Programming

Acceptance: 50.8%

#3185Medium

Count Pairs That Form a Complete Day II

ArrayCountingHash Table

Acceptance: 43.7%

#3186Medium

Maximum Total Damage With Spell Casting

ArrayBinary SearchCounting+4

Acceptance: 45.1%

#3189Medium

Minimum Moves to Get a Peaceful Board

ArrayCounting SortGreedy+1

Acceptance: 75.9%

#3191Medium

Minimum Operations to Make Binary Array Elements Equal to One I

ArrayBit ManipulationPrefix Sum+2

Acceptance: 80.4%

#3192Medium

Minimum Operations to Make Binary Array Elements Equal to One II

ArrayDynamic ProgrammingGreedy

Acceptance: 65.1%

#3195Medium

Find the Minimum Area to Cover All Ones I

ArrayMatrix

Acceptance: 78.2%

#3196Medium

Maximize Total Cost of Alternating Subarrays

ArrayDynamic Programming

Acceptance: 29.6%

#3201Medium

Find the Maximum Length of Valid Subsequence I

ArrayDynamic Programming

Acceptance: 54.9%

#3202Medium

Find the Maximum Length of Valid Subsequence II

ArrayDynamic Programming

Acceptance: 57.2%

#3204Medium

Bitwise User Permissions Analysis

Database

Acceptance: 94.3%

#3205Medium

Maximum Array Hopping Score I

ArrayDynamic ProgrammingGreedy+2

Acceptance: 77.0%

#3207Medium

Maximum Points After Enemy Battles

ArrayGreedy

Acceptance: 33.2%

#3208Medium

Alternating Groups II

ArraySliding Window

Acceptance: 59.9%

#3211Medium

Generate Binary Strings Without Adjacent Zeros

BacktrackingBit ManipulationString

Acceptance: 88.3%

#3212Medium

Count Submatrices With Equal Frequency of X and Y

ArrayMatrixPrefix Sum

Acceptance: 69.5%

#3215Medium

Count Triplets with Even XOR Set Bits II

ArrayBit Manipulation

Acceptance: 62.0%

#3217Medium

Delete Nodes From Linked List Present in Array

ArrayHash TableLinked List

Acceptance: 69.5%

#3218Medium

Minimum Cost for Cutting Cake I

ArrayDynamic ProgrammingGreedy+1

Acceptance: 58.5%

#3220Medium

Odd and Even Transactions

Database

Acceptance: 69.8%

#3221Medium

Maximum Array Hopping Score II

ArrayGreedyMonotonic Stack+1

Acceptance: 60.1%

#3223Medium

Minimum Length of String After Operations

CountingHash TableString

Acceptance: 75.0%

#3224Medium

Minimum Array Changes to Make Differences Equal

ArrayHash TablePrefix Sum

Acceptance: 24.9%

#3227Medium

Vowels Game in a String

BrainteaserGame TheoryMath+1

Acceptance: 77.1%

#3228Medium

Maximum Number of Operations to Move Ones to the End

CountingGreedyString

Acceptance: 67.2%

#3230Medium

Customer Purchasing Behavior Analysis

Database

Acceptance: 37.8%

#3233Medium

Find the Count of Numbers Which Are Not Special

ArrayMathNumber Theory

Acceptance: 28.3%

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