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
2951. Find the Peaks	Easy	75.5%	Array Enumeration	Read
2952. Minimum Number of Coins to be Added	Medium	57.9%	Array Greedy+1	Read
2953. Count Complete Substrings	Hard	31.3%	Hash Table Sliding Window+1	Read
2954. Count the Number of Infection Sequences	Hard	36.7%	Array Combinatorics+1	Read
2955. Number of Same-End Substrings	Medium	61.6%	Array Counting+3	Read
2956. Find Common Elements Between Two Arrays	Easy	84.5%	Array Hash Table	Read
2957. Remove Adjacent Almost-Equal Characters	Medium	53.6%	Dynamic Programming Greedy+1	Read
2958. Length of Longest Subarray With at Most K Frequency	Medium	60.4%	Array Hash Table+1	Read
2959. Number of Possible Sets of Closing Branches	Hard	50.6%	Bit Manipulation Enumeration+3	Read
2960. Count Tested Devices After Test Operations	Easy	78.8%	Array Counting+1	Read
2961. Double Modular Exponentiation	Medium	47.9%	Array Math+1	Read
2962. Count Subarrays Where Max Element Appears at Least K Times	Medium	62.4%	Array Sliding Window	Read
2963. Count the Number of Good Partitions	Hard	49.3%	Array Combinatorics+2	Read
2964. Number of Divisible Triplet Sums	Medium	67.5%	Array Hash Table	Read
2965. Find Missing and Repeated Values	Easy	83.2%	Array Hash Table+2	Read
2966. Divide Array Into Arrays With Max Difference	Medium	79.0%	Array Greedy+1	Read
2967. Minimum Cost to Make Array Equalindromic	Medium	23.4%	Array Binary Search+3	Read
2968. Apply Operations to Maximize Frequency Score	Hard	39.3%	Array Binary Search+3	Read
2969. Minimum Number of Coins for Fruits II	Hard	48.2%	Array Dynamic Programming+3	Read
2970. Count the Number of Incremovable Subarrays I	Easy	56.9%	Array Binary Search+2	Read
2971. Find Polygon With the Largest Perimeter	Medium	65.7%	Array Greedy+2	Read
2972. Count the Number of Incremovable Subarrays II	Hard	39.8%	Array Binary Search+1	Read
2973. Find Number of Coins to Place in Tree Nodes	Hard	37.4%	Depth-First Search Dynamic Programming+3	Read
2974. Minimum Number Game	Easy	85.5%	Array Heap (Priority Queue)+2	Read
2975. Maximum Square Area by Removing Fences From a Field	Medium	49.5%	Array Enumeration+1	Read
2976. Minimum Cost to Convert String I	Medium	63.2%	Array Graph+2	Read
2977. Minimum Cost to Convert String II	Hard	59.1%	Array Dynamic Programming+4	Read
2978. Symmetric Coordinates	Medium	40.8%	Database	Read
2979. Most Expensive Item That Can Not Be Bought	Medium	80.2%	Dynamic Programming Math+1	Read
2980. Check if Bitwise OR Has Trailing Zeros	Easy	71.2%	Array Bit Manipulation	Read
2981. Find Longest Special Substring That Occurs Thrice I	Medium	61.9%	Binary Search Counting+3	Read
2982. Find Longest Special Substring That Occurs Thrice II	Medium	39.2%	Binary Search Counting+3	Read
2983. Palindrome Rearrangement Queries	Hard	25.1%	Hash Table Prefix Sum+1	Read
2984. Find Peak Calling Hours for Each City	Medium	61.1%	Database	Read
2985. Calculate Compressed Mean	Easy	88.0%	Database	Read
2986. Find Third Transaction	Medium	53.0%	Database	Read
2987. Find Expensive Cities	Easy	79.6%	Database	Read
2988. Manager of the Largest Department	Medium	79.4%	Database	Read
2989. Class Performance	Medium	89.9%	Database	Read
2990. Loan Types	Easy	63.2%	Database	Read
2991. Top Three Wineries	Hard	55.8%	Database	Read
2992. Number of Self-Divisible Permutations	Medium	72.0%	Array Backtracking+3	Read
2993. Friday Purchases I	Medium	79.1%	Database	Read
2994. Friday Purchases II	Hard	74.6%	Database	Read
2995. Viewers Turned Streamers	Hard	43.4%	Database	Read
2996. Smallest Missing Integer Greater Than Sequential Prefix Sum	Easy	49.8%	Array Hash Table+1	Read
2997. Minimum Number of Operations to Make Array XOR Equal to K	Medium	85.1%	Array Bit Manipulation	Read
2998. Minimum Number of Operations to Make X and Y Equal	Medium	48.4%	Breadth-First Search Dynamic Programming+1	Read
2999. Count the Number of Powerful Integers	Hard	46.3%	Dynamic Programming Math+1	Read
3000. Maximum Area of Longest Diagonal Rectangle	Easy	45.9%	Array	Read

#2951Easy

Find the Peaks

ArrayEnumeration

Acceptance: 75.5%

#2952Medium

Minimum Number of Coins to be Added

ArrayGreedySorting

Acceptance: 57.9%

#2953Hard

Count Complete Substrings

Hash TableSliding WindowString

Acceptance: 31.3%

#2954Hard

Count the Number of Infection Sequences

ArrayCombinatoricsMath

Acceptance: 36.7%

#2955Medium

Number of Same-End Substrings

ArrayCountingHash Table+2

Acceptance: 61.6%

#2956Easy

Find Common Elements Between Two Arrays

ArrayHash Table

Acceptance: 84.5%

#2957Medium

Remove Adjacent Almost-Equal Characters

Dynamic ProgrammingGreedyString

Acceptance: 53.6%

#2958Medium

Length of Longest Subarray With at Most K Frequency

ArrayHash TableSliding Window

Acceptance: 60.4%

#2959Hard

Number of Possible Sets of Closing Branches

Bit ManipulationEnumerationGraph+2

Acceptance: 50.6%

#2960Easy

Count Tested Devices After Test Operations

ArrayCountingSimulation

Acceptance: 78.8%

#2961Medium

Double Modular Exponentiation

ArrayMathSimulation

Acceptance: 47.9%

#2962Medium

Count Subarrays Where Max Element Appears at Least K Times

ArraySliding Window

Acceptance: 62.4%

#2963Hard

Count the Number of Good Partitions

ArrayCombinatoricsHash Table+1

Acceptance: 49.3%

#2964Medium

Number of Divisible Triplet Sums

ArrayHash Table

Acceptance: 67.5%

#2965Easy

Find Missing and Repeated Values

ArrayHash TableMath+1

Acceptance: 83.2%

#2966Medium

Divide Array Into Arrays With Max Difference

ArrayGreedySorting

Acceptance: 79.0%

#2967Medium

Minimum Cost to Make Array Equalindromic

ArrayBinary SearchGreedy+2

Acceptance: 23.4%

#2968Hard

Apply Operations to Maximize Frequency Score

ArrayBinary SearchPrefix Sum+2

Acceptance: 39.3%

#2969Hard

Minimum Number of Coins for Fruits II

ArrayDynamic ProgrammingHeap (Priority Queue)+2

Acceptance: 48.2%

#2970Easy

Count the Number of Incremovable Subarrays I

ArrayBinary SearchEnumeration+1

Acceptance: 56.9%

#2971Medium

Find Polygon With the Largest Perimeter

ArrayGreedyPrefix Sum+1

Acceptance: 65.7%

#2972Hard

Count the Number of Incremovable Subarrays II

ArrayBinary SearchTwo Pointers

Acceptance: 39.8%

#2973Hard

Find Number of Coins to Place in Tree Nodes

Depth-First SearchDynamic ProgrammingHeap (Priority Queue)+2

Acceptance: 37.4%

#2974Easy

Minimum Number Game

ArrayHeap (Priority Queue)Simulation+1

Acceptance: 85.5%

#2975Medium

Maximum Square Area by Removing Fences From a Field

ArrayEnumerationHash Table

Acceptance: 49.5%

#2976Medium

Minimum Cost to Convert String I

ArrayGraphShortest Path+1

Acceptance: 63.2%

#2977Hard

Minimum Cost to Convert String II

ArrayDynamic ProgrammingGraph+3

Acceptance: 59.1%

#2978Medium

Symmetric Coordinates

Database

Acceptance: 40.8%

#2979Medium

Most Expensive Item That Can Not Be Bought

Dynamic ProgrammingMathNumber Theory

Acceptance: 80.2%

#2980Easy

Check if Bitwise OR Has Trailing Zeros

ArrayBit Manipulation

Acceptance: 71.2%

#2981Medium

Find Longest Special Substring That Occurs Thrice I

Binary SearchCountingHash Table+2

Acceptance: 61.9%

#2982Medium

Find Longest Special Substring That Occurs Thrice II

Binary SearchCountingHash Table+2

Acceptance: 39.2%

#2983Hard

Palindrome Rearrangement Queries

Hash TablePrefix SumString

Acceptance: 25.1%

#2984Medium

Find Peak Calling Hours for Each City

Database

Acceptance: 61.1%

#2985Easy

Calculate Compressed Mean

Database

Acceptance: 88.0%

#2986Medium

Find Third Transaction

Database

Acceptance: 53.0%

#2987Easy

Find Expensive Cities

Database

Acceptance: 79.6%

#2988Medium

Manager of the Largest Department

Database

Acceptance: 79.4%

#2989Medium

Class Performance

Database

Acceptance: 89.9%

#2990Easy

Loan Types

Database

Acceptance: 63.2%

#2991Hard

Top Three Wineries

Database

Acceptance: 55.8%

#2992Medium

Number of Self-Divisible Permutations

ArrayBacktrackingBit Manipulation+2

Acceptance: 72.0%

#2993Medium

Friday Purchases I

Database

Acceptance: 79.1%

#2994Hard

Friday Purchases II

Database

Acceptance: 74.6%

#2995Hard

Viewers Turned Streamers

Database

Acceptance: 43.4%

#2996Easy

Smallest Missing Integer Greater Than Sequential Prefix Sum

ArrayHash TableSorting

Acceptance: 49.8%

#2997Medium

Minimum Number of Operations to Make Array XOR Equal to K

ArrayBit Manipulation

Acceptance: 85.1%

#2998Medium

Minimum Number of Operations to Make X and Y Equal

Breadth-First SearchDynamic ProgrammingMemoization

Acceptance: 48.4%

#2999Hard

Count the Number of Powerful Integers

Dynamic ProgrammingMathString

Acceptance: 46.3%

#3000Easy

Maximum Area of Longest Diagonal Rectangle

Array

Acceptance: 45.9%

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