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
3758. Convert Number Words to Digits	Medium	67.7%	String Trie	Read
3789. Minimum Cost to Acquire Required Items	Medium	34.8%	Greedy Math	Read
3771. Total Score of Dungeon Runs	Medium	30.6%	Array Binary Search+1	Read
3768. Minimum Inversion Count in Subarrays of Fixed Length	Hard	40.3%	Array Segment Tree+1	Read
3801. Minimum Cost to Merge Sorted Lists	Hard	33.2%	Array Binary Search+3	Read
3811. Number of Alternating XOR Partitions	Medium	27.3%	Array Bit Manipulation+2	Read
3759. Count Elements With at Least K Greater Values	Medium	31.9%	Array Binary Search+3	Read
3749. Evaluate Valid Expressions	Hard	69.4%	Divide and Conquer Hash Table+3	Read
3761. Minimum Absolute Distance Between Mirror Pairs	Medium	59.1%	Array Hash Table+1	Read
3784. Minimum Deletion Cost to Make All Characters Equal	Medium	55.0%	Array Enumeration+2	Read
3839. Number of Prefix Connected Groups	Medium	60.5%	Array Counting+2	Read
3756. Concatenate Non-Zero Digits and Multiply by Sum II	Medium	42.7%	Math Prefix Sum+1	Read
3754. Concatenate Non-Zero Digits and Multiply by Sum I	Easy	66.2%	Math	Read
3757. Number of Effective Subsequences	Hard	32.4%	Array Bit Manipulation+3	Read
3802. Number of Ways to Paint Sheets	Hard	67.3%		Read
3781. Maximum Score After Binary Swaps	Medium	35.0%	Array Greedy+2	Read
3804. Number of Centered Subarrays	Medium	67.5%	Array Enumeration+1	Read
3753. Total Waviness of Numbers in Range II	Hard	56.2%	Dynamic Programming Math	Read
3778. Minimum Distance Excluding One Maximum Weighted Edge	Medium	46.8%		Read
3750. Minimum Number of Flips to Reverse Binary String	Easy	76.7%	Bit Manipulation Math+2	Read
3828. Final Element After Subarray Deletions	Medium	40.9%	Array Brainteaser+2	Read
3826. Minimum Partition Score	Hard	32.6%	Array Divide and Conquer+4	Read
3741. Minimum Distance Between Three Equal Elements II	Medium	74.3%	Array Hash Table	Read
3829. Design Ride Sharing System	Medium	62.6%	Data Stream Design+2	Read
3736. Minimum Moves to Equal Array Elements III	Easy	81.0%	Array Math	Read
3740. Minimum Distance Between Three Equal Elements I	Easy	73.4%	Array Hash Table	Read
3744. Find Kth Character in Expanded String	Medium	55.8%	String	Read
3745. Maximize Expression of Three Elements	Easy	72.3%	Array Enumeration+2	Read
3748. Count Stable Subarrays	Hard	33.0%	Array Binary Search+1	Read
3730. Maximum Calories Burnt from Jumps	Medium	72.2%	Array Greedy+2	Read
3717. Minimum Operations to Make the Array Beautiful	Medium	37.5%	Array Dynamic Programming	Read
3731. Find Missing Elements	Easy	88.6%	Array Hash Table+1	Read
3735. Lexicographically Smallest String After Reverse II	Hard	48.3%	Binary Search Hash Function+3	Read
3732. Maximum Product of Three Elements After One Replacement	Medium	47.8%	Array Greedy+2	Read
3765. Complete Prime Number	Medium	36.9%	Enumeration Math+1	Read
3766. Minimum Operations to Make Binary Palindrome	Medium	51.2%	Array Binary Search+2	Read
3738. Longest Non-Decreasing Subarray After Replacing at Most One Element	Medium	22.9%	Array Dynamic Programming	Read
3877. Minimum Removals to Achieve Target XOR	Medium	41.9%	Array Bit Manipulation+1	Read
3791. Number of Balanced Integers in a Range	Hard	36.3%	Dynamic Programming	Read
3746. Minimum String Length After Balanced Removals	Medium	77.6%	Counting Stack+1	Read
3767. Maximize Points After Choosing K Tasks	Medium	59.1%	Array Greedy+2	Read
3760. Maximum Substrings With Distinct Start	Medium	91.4%	Hash Table String	Read
3816. Lexicographically Smallest String After Deleting Duplicate Characters	Hard	20.9%	Greedy Hash Table+3	Read
3770. Largest Prime from Consecutive Prime Sum	Medium	39.0%	Array Math+1	Read
3723. Maximize Sum of Squares of Digits	Medium	57.9%	Greedy Math	Read
3728. Stable Subarrays With Equal Boundary and Interior Sum	Medium	26.6%	Array Hash Table+1	Read
3711. Maximum Transactions Without Negative Balance	Medium	46.1%	Array Greedy+1	Read
3718. Smallest Missing Multiple of K	Easy	71.5%	Array Hash Table	Read
3814. Maximum Capacity Within Budget	Medium	20.7%	Array Binary Search+2	Read
3727. Maximum Alternating Sum of Squares	Medium	61.3%	Array Greedy+1	Read

#3758Medium

Convert Number Words to Digits

StringTrie

Acceptance: 67.7%

#3789Medium

Minimum Cost to Acquire Required Items

GreedyMath

Acceptance: 34.8%

#3771Medium

Total Score of Dungeon Runs

ArrayBinary SearchPrefix Sum

Acceptance: 30.6%

#3768Hard

Minimum Inversion Count in Subarrays of Fixed Length

ArraySegment TreeSliding Window

Acceptance: 40.3%

#3801Hard

Minimum Cost to Merge Sorted Lists

ArrayBinary SearchBit Manipulation+2

Acceptance: 33.2%

#3811Medium

Number of Alternating XOR Partitions

ArrayBit ManipulationDynamic Programming+1

Acceptance: 27.3%

#3759Medium

Count Elements With at Least K Greater Values

ArrayBinary SearchDivide and Conquer+2

Acceptance: 31.9%

#3749Hard

Evaluate Valid Expressions

Divide and ConquerHash TableMath+2

Acceptance: 69.4%

#3761Medium

Minimum Absolute Distance Between Mirror Pairs

ArrayHash TableMath

Acceptance: 59.1%

#3784Medium

Minimum Deletion Cost to Make All Characters Equal

ArrayEnumerationHash Table+1

Acceptance: 55.0%

#3839Medium

Number of Prefix Connected Groups

ArrayCountingHash Table+1

Acceptance: 60.5%

#3756Medium

Concatenate Non-Zero Digits and Multiply by Sum II

MathPrefix SumString

Acceptance: 42.7%

#3754Easy

Concatenate Non-Zero Digits and Multiply by Sum I

Math

Acceptance: 66.2%

#3757Hard

Number of Effective Subsequences

ArrayBit ManipulationCombinatorics+2

Acceptance: 32.4%

#3802Hard

Number of Ways to Paint Sheets

Acceptance: 67.3%

#3781Medium

Maximum Score After Binary Swaps

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 35.0%

#3804Medium

Number of Centered Subarrays

ArrayEnumerationHash Table

Acceptance: 67.5%

#3753Hard

Total Waviness of Numbers in Range II

Dynamic ProgrammingMath

Acceptance: 56.2%

#3778Medium

Minimum Distance Excluding One Maximum Weighted Edge

Acceptance: 46.8%

#3750Easy

Minimum Number of Flips to Reverse Binary String

Bit ManipulationMathString+1

Acceptance: 76.7%

#3828Medium

Final Element After Subarray Deletions

ArrayBrainteaserGame Theory+1

Acceptance: 40.9%

#3826Hard

Minimum Partition Score

ArrayDivide and ConquerDynamic Programming+3

Acceptance: 32.6%

#3741Medium

Minimum Distance Between Three Equal Elements II

ArrayHash Table

Acceptance: 74.3%

#3829Medium

Design Ride Sharing System

Data StreamDesignHash Table+1

Acceptance: 62.6%

#3736Easy

Minimum Moves to Equal Array Elements III

ArrayMath

Acceptance: 81.0%

#3740Easy

Minimum Distance Between Three Equal Elements I

ArrayHash Table

Acceptance: 73.4%

#3744Medium

Find Kth Character in Expanded String

String

Acceptance: 55.8%

#3745Easy

Maximize Expression of Three Elements

ArrayEnumerationGreedy+1

Acceptance: 72.3%

#3748Hard

Count Stable Subarrays

ArrayBinary SearchPrefix Sum

Acceptance: 33.0%

#3730Medium

Maximum Calories Burnt from Jumps

ArrayGreedySorting+1

Acceptance: 72.2%

#3717Medium

Minimum Operations to Make the Array Beautiful

ArrayDynamic Programming

Acceptance: 37.5%

#3731Easy

Find Missing Elements

ArrayHash TableSorting

Acceptance: 88.6%

#3735Hard

Lexicographically Smallest String After Reverse II

Binary SearchHash FunctionRolling Hash+2

Acceptance: 48.3%

#3732Medium

Maximum Product of Three Elements After One Replacement

ArrayGreedyMath+1

Acceptance: 47.8%

#3765Medium

Complete Prime Number

EnumerationMathNumber Theory

Acceptance: 36.9%

#3766Medium

Minimum Operations to Make Binary Palindrome

ArrayBinary SearchBit Manipulation+1

Acceptance: 51.2%

#3738Medium

Longest Non-Decreasing Subarray After Replacing at Most One Element

ArrayDynamic Programming

Acceptance: 22.9%

#3877Medium

Minimum Removals to Achieve Target XOR

ArrayBit ManipulationDynamic Programming

Acceptance: 41.9%

#3791Hard

Number of Balanced Integers in a Range

Dynamic Programming

Acceptance: 36.3%

#3746Medium

Minimum String Length After Balanced Removals

CountingStackString

Acceptance: 77.6%

#3767Medium

Maximize Points After Choosing K Tasks

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 59.1%

#3760Medium

Maximum Substrings With Distinct Start

Hash TableString

Acceptance: 91.4%

#3816Hard

Lexicographically Smallest String After Deleting Duplicate Characters

GreedyHash TableMonotonic Stack+2

Acceptance: 20.9%

#3770Medium

Largest Prime from Consecutive Prime Sum

ArrayMathNumber Theory

Acceptance: 39.0%

#3723Medium

Maximize Sum of Squares of Digits

GreedyMath

Acceptance: 57.9%

#3728Medium

Stable Subarrays With Equal Boundary and Interior Sum

ArrayHash TablePrefix Sum

Acceptance: 26.6%

#3711Medium

Maximum Transactions Without Negative Balance

ArrayGreedyHeap (Priority Queue)

Acceptance: 46.1%

#3718Easy

Smallest Missing Multiple of K

ArrayHash Table

Acceptance: 71.5%

#3814Medium

Maximum Capacity Within Budget

ArrayBinary SearchSorting+1

Acceptance: 20.7%

#3727Medium

Maximum Alternating Sum of Squares

ArrayGreedySorting

Acceptance: 61.3%

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Master DSA with Step-by-Step Solutions

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