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
1801. Number of Orders in the Backlog	Medium	54.3%	Array Heap (Priority Queue)+1	Read
1802. Maximum Value at a Given Index in a Bounded Array	Medium	39.0%	Binary Search Greedy	Read
1803. Count Pairs With XOR in a Range	Hard	46.3%	Array Bit Manipulation+1	Read
1804. Implement Trie II (Prefix Tree)	Medium	63.6%	Design Hash Table+2	Read
1805. Number of Different Integers in a String	Easy	40.2%	Hash Table String	Read
1806. Minimum Number of Operations to Reinitialize a Permutation	Medium	72.9%	Array Math+1	Read
1807. Evaluate the Bracket Pairs of a String	Medium	69.4%	Array Hash Table+1	Read
1808. Maximize Number of Nice Divisors	Hard	36.7%	Math Number Theory+1	Read
1809. Ad-Free Sessions	Easy	58.6%	Database	Read
1810. Minimum Path Cost in a Hidden Grid	Medium	58.7%	Breadth-First Search Depth-First Search+3	Read
1811. Find Interview Candidates	Medium	60.8%	Database	Read
1812. Determine Color of a Chessboard Square	Easy	79.8%	Math String	Read
1813. Sentence Similarity III	Medium	48.8%	Array String+1	Read
1814. Count Nice Pairs in an Array	Medium	48.6%	Array Counting+2	Read
1815. Maximum Number of Groups Getting Fresh Donuts	Hard	41.7%	Array Bit Manipulation+3	Read
1816. Truncate Sentence	Easy	86.7%	Array String	Read
1817. Finding the Users Active Minutes	Medium	81.0%	Array Hash Table	Read
1818. Minimum Absolute Sum Difference	Medium	32.9%	Array Binary Search+2	Read
1819. Number of Different Subsequences GCDs	Hard	47.2%	Array Counting+2	Read
1820. Maximum Number of Accepted Invitations	Medium	52.4%	Array Depth-First Search+2	Read
1821. Find Customers With Positive Revenue this Year	Easy	87.7%	Database	Read
1822. Sign of the Product of an Array	Easy	64.8%	Array Math	Read
1823. Find the Winner of the Circular Game	Medium	81.9%	Array Math+3	Read
1824. Minimum Sideway Jumps	Medium	51.6%	Array Dynamic Programming+1	Read
1825. Finding MK Average	Hard	38.7%	Data Stream Design+3	Read
1826. Faulty Sensor	Easy	50.2%	Array Two Pointers	Read
1827. Minimum Operations to Make the Array Increasing	Easy	81.9%	Array Greedy	Read
1828. Queries on Number of Points Inside a Circle	Medium	86.9%	Array Geometry+1	Read
1829. Maximum XOR for Each Query	Medium	84.7%	Array Bit Manipulation+1	Read
1830. Minimum Number of Operations to Make String Sorted	Hard	50.4%	Combinatorics Math+1	Read
1831. Maximum Transaction Each Day	Medium	82.1%	Database	Read
1832. Check if the Sentence Is Pangram	Easy	84.2%	Hash Table String	Read
1833. Maximum Ice Cream Bars	Medium	77.2%	Array Counting Sort+2	Read
1834. Single-Threaded CPU	Medium	48.1%	Array Heap (Priority Queue)+1	Read
1835. Find XOR Sum of All Pairs Bitwise AND	Hard	62.6%	Array Bit Manipulation+1	Read
1836. Remove Duplicates From an Unsorted Linked List	Medium	75.6%	Hash Table Linked List	Read
1837. Sum of Digits in Base K	Easy	79.2%	Math	Read
1838. Frequency of the Most Frequent Element	Medium	44.7%	Array Binary Search+4	Read
1839. Longest Substring Of All Vowels in Order	Medium	52.3%	Sliding Window String	Read
1840. Maximum Building Height	Hard	67.1%	Array Math+1	Read
1841. League Statistics	Medium	53.4%	Database	Read
1842. Next Palindrome Using Same Digits	Hard	54.2%	String Two Pointers	Read
1843. Suspicious Bank Accounts	Medium	45.0%	Database	Read
1844. Replace All Digits with Characters	Easy	82.7%	String	Read
1845. Seat Reservation Manager	Medium	67.1%	Design Heap (Priority Queue)	Read
1846. Maximum Element After Decreasing and Rearranging	Medium	69.2%	Array Greedy+1	Read
1847. Closest Room	Hard	41.9%	Array Binary Search+2	Read
1848. Minimum Distance to the Target Element	Easy	64.5%	Array	Read
1849. Splitting a String Into Descending Consecutive Values	Medium	37.5%	Backtracking String	Read
1850. Minimum Adjacent Swaps to Reach the Kth Smallest Number	Medium	72.0%	Greedy String+1	Read

#1801Medium

Number of Orders in the Backlog

ArrayHeap (Priority Queue)Simulation

Acceptance: 54.3%

#1802Medium

Maximum Value at a Given Index in a Bounded Array

Binary SearchGreedy

Acceptance: 39.0%

#1803Hard

Count Pairs With XOR in a Range

ArrayBit ManipulationTrie

Acceptance: 46.3%

#1804Medium

Implement Trie II (Prefix Tree)

DesignHash TableString+1

Acceptance: 63.6%

#1805Easy

Number of Different Integers in a String

Hash TableString

Acceptance: 40.2%

#1806Medium

Minimum Number of Operations to Reinitialize a Permutation

ArrayMathSimulation

Acceptance: 72.9%

#1807Medium

Evaluate the Bracket Pairs of a String

ArrayHash TableString

Acceptance: 69.4%

#1808Hard

Maximize Number of Nice Divisors

MathNumber TheoryRecursion

Acceptance: 36.7%

#1809Easy

Ad-Free Sessions

Database

Acceptance: 58.6%

#1810Medium

Minimum Path Cost in a Hidden Grid

Breadth-First SearchDepth-First SearchGraph+2

Acceptance: 58.7%

#1811Medium

Find Interview Candidates

Database

Acceptance: 60.8%

#1812Easy

Determine Color of a Chessboard Square

MathString

Acceptance: 79.8%

#1813Medium

Sentence Similarity III

ArrayStringTwo Pointers

Acceptance: 48.8%

#1814Medium

Count Nice Pairs in an Array

ArrayCountingHash Table+1

Acceptance: 48.6%

#1815Hard

Maximum Number of Groups Getting Fresh Donuts

ArrayBit ManipulationBitmask+2

Acceptance: 41.7%

#1816Easy

Truncate Sentence

ArrayString

Acceptance: 86.7%

#1817Medium

Finding the Users Active Minutes

ArrayHash Table

Acceptance: 81.0%

#1818Medium

Minimum Absolute Sum Difference

ArrayBinary SearchOrdered Set+1

Acceptance: 32.9%

#1819Hard

Number of Different Subsequences GCDs

ArrayCountingMath+1

Acceptance: 47.2%

#1820Medium

Maximum Number of Accepted Invitations

ArrayDepth-First SearchGraph+1

Acceptance: 52.4%

#1821Easy

Find Customers With Positive Revenue this Year

Database

Acceptance: 87.7%

#1822Easy

Sign of the Product of an Array

ArrayMath

Acceptance: 64.8%

#1823Medium

Find the Winner of the Circular Game

ArrayMathQueue+2

Acceptance: 81.9%

#1824Medium

Minimum Sideway Jumps

ArrayDynamic ProgrammingGreedy

Acceptance: 51.6%

#1825Hard

Finding MK Average

Data StreamDesignHeap (Priority Queue)+2

Acceptance: 38.7%

#1826Easy

Faulty Sensor

ArrayTwo Pointers

Acceptance: 50.2%

#1827Easy

Minimum Operations to Make the Array Increasing

ArrayGreedy

Acceptance: 81.9%

#1828Medium

Queries on Number of Points Inside a Circle

ArrayGeometryMath

Acceptance: 86.9%

#1829Medium

Maximum XOR for Each Query

ArrayBit ManipulationPrefix Sum

Acceptance: 84.7%

#1830Hard

Minimum Number of Operations to Make String Sorted

CombinatoricsMathString

Acceptance: 50.4%

#1831Medium

Maximum Transaction Each Day

Database

Acceptance: 82.1%

#1832Easy

Check if the Sentence Is Pangram

Hash TableString

Acceptance: 84.2%

#1833Medium

Maximum Ice Cream Bars

ArrayCounting SortGreedy+1

Acceptance: 77.2%

#1834Medium

Single-Threaded CPU

ArrayHeap (Priority Queue)Sorting

Acceptance: 48.1%

#1835Hard

Find XOR Sum of All Pairs Bitwise AND

ArrayBit ManipulationMath

Acceptance: 62.6%

#1836Medium

Remove Duplicates From an Unsorted Linked List

Hash TableLinked List

Acceptance: 75.6%

#1837Easy

Sum of Digits in Base K

Math

Acceptance: 79.2%

#1838Medium

Frequency of the Most Frequent Element

ArrayBinary SearchGreedy+3

Acceptance: 44.7%

#1839Medium

Longest Substring Of All Vowels in Order

Sliding WindowString

Acceptance: 52.3%

#1840Hard

Maximum Building Height

ArrayMathSorting

Acceptance: 67.1%

#1841Medium

League Statistics

Database

Acceptance: 53.4%

#1842Hard

Next Palindrome Using Same Digits

StringTwo Pointers

Acceptance: 54.2%

#1843Medium

Suspicious Bank Accounts

Database

Acceptance: 45.0%

#1844Easy

Replace All Digits with Characters

String

Acceptance: 82.7%

#1845Medium

Seat Reservation Manager

DesignHeap (Priority Queue)

Acceptance: 67.1%

#1846Medium

Maximum Element After Decreasing and Rearranging

ArrayGreedySorting

Acceptance: 69.2%

#1847Hard

Closest Room

ArrayBinary SearchOrdered Set+1

Acceptance: 41.9%

#1848Easy

Minimum Distance to the Target Element

Array

Acceptance: 64.5%

#1849Medium

Splitting a String Into Descending Consecutive Values

BacktrackingString

Acceptance: 37.5%

#1850Medium

Minimum Adjacent Swaps to Reach the Kth Smallest Number

GreedyStringTwo Pointers

Acceptance: 72.0%

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Master DSA with Step-by-Step Solutions

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