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
801. Minimum Swaps To Make Sequences Increasing	Hard	42.0%	Array Dynamic Programming	Read
802. Find Eventual Safe States	Medium	71.6%	Breadth-First Search Depth-First Search+2	Read
803. Bricks Falling When Hit	Hard	37.7%	Array Matrix+1	Read
804. Unique Morse Code Words	Easy	83.6%	Array Hash Table+1	Read
805. Split Array With Same Average	Hard	27.5%	Array Bit Manipulation+3	Read
806. Number of Lines To Write String	Easy	72.9%	Array String	Read
807. Max Increase to Keep City Skyline	Medium	86.2%	Array Greedy+1	Read
808. Soup Servings	Medium	59.7%	Dynamic Programming Math+1	Read
809. Expressive Words	Medium	46.8%	Array String+1	Read
810. Chalkboard XOR Game	Hard	66.7%	Array Bit Manipulation+3	Read
811. Subdomain Visit Count	Medium	77.2%	Array Counting+2	Read
812. Largest Triangle Area	Easy	72.1%	Array Geometry+1	Read
813. Largest Sum of Averages	Medium	55.5%	Array Dynamic Programming+1	Read
814. Binary Tree Pruning	Medium	72.3%	Binary Tree Depth-First Search+1	Read
815. Bus Routes	Hard	47.3%	Array Breadth-First Search+1	Read
816. Ambiguous Coordinates	Medium	56.4%	Backtracking Enumeration+1	Read
817. Linked List Components	Medium	57.8%	Array Hash Table+1	Read
818. Race Car	Hard	44.7%	Dynamic Programming	Read
819. Most Common Word	Easy	45.0%	Array Counting+2	Read
820. Short Encoding of Words	Medium	61.0%	Array Hash Table+2	Read
821. Shortest Distance to a Character	Easy	72.7%	Array String+1	Read
822. Card Flipping Game	Medium	50.7%	Array Hash Table	Read
823. Binary Trees With Factors	Medium	52.9%	Array Dynamic Programming+2	Read
824. Goat Latin	Easy	69.9%	String	Read
825. Friends Of Appropriate Ages	Medium	49.9%	Array Binary Search+2	Read
826. Most Profit Assigning Work	Medium	56.4%	Array Binary Search+3	Read
827. Making A Large Island	Hard	57.0%	Array Breadth-First Search+3	Read
828. Count Unique Characters of All Substrings of a Given String	Hard	53.5%	Dynamic Programming Hash Table+1	Read
829. Consecutive Numbers Sum	Hard	42.6%	Enumeration Math	Read
830. Positions of Large Groups	Easy	54.4%	String	Read
831. Masking Personal Information	Medium	56.2%	String	Read
832. Flipping an Image	Easy	83.6%	Array Bit Manipulation+3	Read
833. Find And Replace in String	Medium	50.9%	Array Hash Table+2	Read
834. Sum of Distances in Tree	Hard	65.8%	Depth-First Search Dynamic Programming+2	Read
835. Image Overlap	Medium	70.6%	Array Matrix	Read
836. Rectangle Overlap	Easy	53.0%	Geometry Math	Read
837. New 21 Game	Medium	52.0%	Dynamic Programming Math+2	Read
838. Push Dominoes	Medium	63.0%	Dynamic Programming String+1	Read
839. Similar String Groups	Hard	56.1%	Array Breadth-First Search+4	Read
840. Magic Squares In Grid	Medium	55.1%	Array Hash Table+2	Read
841. Keys and Rooms	Medium	76.2%	Breadth-First Search Depth-First Search+1	Read
842. Split Array into Fibonacci Sequence	Medium	40.3%	Backtracking String	Read
843. Guess the Word	Hard	36.9%	Array Game Theory+3	Read
844. Backspace String Compare	Easy	49.9%	Simulation Stack+2	Read
845. Longest Mountain in Array	Medium	42.0%	Array Dynamic Programming+2	Read
846. Hand of Straights	Medium	57.9%	Array Greedy+2	Read
847. Shortest Path Visiting All Nodes	Hard	65.9%	Bit Manipulation Bitmask+3	Read
848. Shifting Letters	Medium	46.1%	Array Prefix Sum+1	Read
849. Maximize Distance to Closest Person	Medium	49.7%	Array	Read
850. Rectangle Area II	Hard	56.7%	Array Line Sweep+2	Read

#801Hard

Minimum Swaps To Make Sequences Increasing

ArrayDynamic Programming

Acceptance: 42.0%

#802Medium

Find Eventual Safe States

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 71.6%

#803Hard

Bricks Falling When Hit

ArrayMatrixUnion Find

Acceptance: 37.7%

#804Easy

Unique Morse Code Words

ArrayHash TableString

Acceptance: 83.6%

#805Hard

Split Array With Same Average

ArrayBit ManipulationBitmask+2

Acceptance: 27.5%

#806Easy

Number of Lines To Write String

ArrayString

Acceptance: 72.9%

#807Medium

Max Increase to Keep City Skyline

ArrayGreedyMatrix

Acceptance: 86.2%

#808Medium

Soup Servings

Dynamic ProgrammingMathProbability and Statistics

Acceptance: 59.7%

#809Medium

Expressive Words

ArrayStringTwo Pointers

Acceptance: 46.8%

#810Hard

Chalkboard XOR Game

ArrayBit ManipulationBrainteaser+2

Acceptance: 66.7%

#811Medium

Subdomain Visit Count

ArrayCountingHash Table+1

Acceptance: 77.2%

#812Easy

Largest Triangle Area

ArrayGeometryMath

Acceptance: 72.1%

#813Medium

Largest Sum of Averages

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 55.5%

#814Medium

Binary Tree Pruning

Binary TreeDepth-First SearchTree

Acceptance: 72.3%

#815Hard

Bus Routes

ArrayBreadth-First SearchHash Table

Acceptance: 47.3%

#816Medium

Ambiguous Coordinates

BacktrackingEnumerationString

Acceptance: 56.4%

#817Medium

Linked List Components

ArrayHash TableLinked List

Acceptance: 57.8%

#818Hard

Race Car

Dynamic Programming

Acceptance: 44.7%

#819Easy

Most Common Word

ArrayCountingHash Table+1

Acceptance: 45.0%

#820Medium

Short Encoding of Words

ArrayHash TableString+1

Acceptance: 61.0%

#821Easy

Shortest Distance to a Character

ArrayStringTwo Pointers

Acceptance: 72.7%

#822Medium

Card Flipping Game

ArrayHash Table

Acceptance: 50.7%

#823Medium

Binary Trees With Factors

ArrayDynamic ProgrammingHash Table+1

Acceptance: 52.9%

#824Easy

Goat Latin

String

Acceptance: 69.9%

#825Medium

Friends Of Appropriate Ages

ArrayBinary SearchSorting+1

Acceptance: 49.9%

#826Medium

Most Profit Assigning Work

ArrayBinary SearchGreedy+2

Acceptance: 56.4%

#827Hard

Making A Large Island

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 57.0%

#828Hard

Count Unique Characters of All Substrings of a Given String

Dynamic ProgrammingHash TableString

Acceptance: 53.5%

#829Hard

Consecutive Numbers Sum

EnumerationMath

Acceptance: 42.6%

#830Easy

Positions of Large Groups

String

Acceptance: 54.4%

#831Medium

Masking Personal Information

String

Acceptance: 56.2%

#832Easy

Flipping an Image

ArrayBit ManipulationMatrix+2

Acceptance: 83.6%

#833Medium

Find And Replace in String

ArrayHash TableSorting+1

Acceptance: 50.9%

#834Hard

Sum of Distances in Tree

Depth-First SearchDynamic ProgrammingGraph+1

Acceptance: 65.8%

#835Medium

Image Overlap

ArrayMatrix

Acceptance: 70.6%

#836Easy

Rectangle Overlap

GeometryMath

Acceptance: 53.0%

#837Medium

New 21 Game

Dynamic ProgrammingMathProbability and Statistics+1

Acceptance: 52.0%

#838Medium

Push Dominoes

Dynamic ProgrammingStringTwo Pointers

Acceptance: 63.0%

#839Hard

Similar String Groups

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 56.1%

#840Medium

Magic Squares In Grid

ArrayHash TableMath+1

Acceptance: 55.1%

#841Medium

Keys and Rooms

Breadth-First SearchDepth-First SearchGraph

Acceptance: 76.2%

#842Medium

Split Array into Fibonacci Sequence

BacktrackingString

Acceptance: 40.3%

#843Hard

Guess the Word

ArrayGame TheoryInteractive+2

Acceptance: 36.9%

#844Easy

Backspace String Compare

SimulationStackString+1

Acceptance: 49.9%

#845Medium

Longest Mountain in Array

ArrayDynamic ProgrammingEnumeration+1

Acceptance: 42.0%

#846Medium

Hand of Straights

ArrayGreedyHash Table+1

Acceptance: 57.9%

#847Hard

Shortest Path Visiting All Nodes

Bit ManipulationBitmaskBreadth-First Search+2

Acceptance: 65.9%

#848Medium

Shifting Letters

ArrayPrefix SumString

Acceptance: 46.1%

#849Medium

Maximize Distance to Closest Person

Array

Acceptance: 49.7%

#850Hard

Rectangle Area II

ArrayLine SweepOrdered Set+1

Acceptance: 56.7%

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Master DSA with Step-by-Step Solutions

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