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
851. Loud and Rich	Medium	63.9%	Array Depth-First Search+2	Read
852. Peak Index in a Mountain Array	Medium	66.9%	Array Binary Search	Read
853. Car Fleet	Medium	55.5%	Array Monotonic Stack+2	Read
854. K-Similar Strings	Hard	41.3%	Breadth-First Search String	Read
855. Exam Room	Medium	43.6%	Design Heap (Priority Queue)+1	Read
856. Score of Parentheses	Medium	63.9%	Stack String	Read
857. Minimum Cost to Hire K Workers	Hard	63.5%	Array Greedy+2	Read
858. Mirror Reflection	Medium	62.3%	Geometry Math+1	Read
859. Buddy Strings	Easy	34.0%	Hash Table String	Read
860. Lemonade Change	Easy	59.0%	Array Greedy	Read
861. Score After Flipping Matrix	Medium	80.3%	Array Bit Manipulation+2	Read
862. Shortest Subarray with Sum at Least K	Hard	32.7%	Array Binary Search+5	Read
863. All Nodes Distance K in Binary Tree	Medium	68.1%	Binary Tree Breadth-First Search+3	Read
864. Shortest Path to Get All Keys	Hard	55.0%	Array Bit Manipulation+2	Read
865. Smallest Subtree with all the Deepest Nodes	Medium	77.5%	Binary Tree Breadth-First Search+3	Read
866. Prime Palindrome	Medium	28.6%	Math Number Theory	Read
867. Transpose Matrix	Easy	76.8%	Array Matrix+1	Read
868. Binary Gap	Easy	74.2%	Bit Manipulation	Read
869. Reordered Power of 2	Medium	66.0%	Counting Enumeration+3	Read
870. Advantage Shuffle	Medium	55.0%	Array Greedy+2	Read
871. Minimum Number of Refueling Stops	Hard	41.8%	Array Dynamic Programming+2	Read
872. Leaf-Similar Trees	Easy	70.0%	Binary Tree Depth-First Search+1	Read
873. Length of Longest Fibonacci Subsequence	Medium	57.5%	Array Dynamic Programming+1	Read
874. Walking Robot Simulation	Medium	64.5%	Array Hash Table+1	Read
875. Koko Eating Bananas	Medium	50.4%	Array Binary Search	Read
876. Middle of the Linked List	Easy	82.3%	Linked List Two Pointers	Read
877. Stone Game	Medium	77.0%	Array Dynamic Programming+2	Read
878. Nth Magical Number	Hard	37.1%	Binary Search Math	Read
879. Profitable Schemes	Hard	48.1%	Array Dynamic Programming	Read
880. Decoded String at Index	Medium	37.3%	Stack String	Read
881. Boats to Save People	Medium	62.1%	Array Greedy+2	Read
882. Reachable Nodes In Subdivided Graph	Hard	52.5%	Graph Heap (Priority Queue)+1	Read
883. Projection Area of 3D Shapes	Easy	76.3%	Array Geometry+2	Read
884. Uncommon Words from Two Sentences	Easy	75.8%	Counting Hash Table+1	Read
885. Spiral Matrix III	Medium	84.6%	Array Matrix+1	Read
886. Possible Bipartition	Medium	53.0%	Breadth-First Search Depth-First Search+2	Read
887. Super Egg Drop	Hard	30.6%	Binary Search Dynamic Programming+1	Read
888. Fair Candy Swap	Easy	65.3%	Array Binary Search+2	Read
889. Construct Binary Tree from Preorder and Postorder Traversal	Medium	78.0%	Array Binary Tree+3	Read
890. Find and Replace Pattern	Medium	76.8%	Array Hash Table+1	Read
891. Sum of Subsequence Widths	Hard	41.1%	Array Math+1	Read
892. Surface Area of 3D Shapes	Easy	71.2%	Array Geometry+2	Read
893. Groups of Special-Equivalent Strings	Medium	73.5%	Array Hash Table+2	Read
894. All Possible Full Binary Trees	Medium	82.8%	Binary Tree Dynamic Programming+3	Read
895. Maximum Frequency Stack	Hard	67.1%	Design Hash Table+2	Read
896. Monotonic Array	Easy	62.3%	Array	Read
897. Increasing Order Search Tree	Easy	79.1%	Binary Search Tree Binary Tree+3	Read
898. Bitwise ORs of Subarrays	Medium	56.8%	Array Bit Manipulation+1	Read
899. Orderly Queue	Hard	66.8%	Math Sorting+1	Read
900. RLE Iterator	Medium	59.6%	Array Counting+2	Read

#851Medium

Loud and Rich

ArrayDepth-First SearchGraph+1

Acceptance: 63.9%

#852Medium

Peak Index in a Mountain Array

ArrayBinary Search

Acceptance: 66.9%

#853Medium

Car Fleet

ArrayMonotonic StackSorting+1

Acceptance: 55.5%

#854Hard

K-Similar Strings

Breadth-First SearchString

Acceptance: 41.3%

#855Medium

Exam Room

DesignHeap (Priority Queue)Ordered Set

Acceptance: 43.6%

#856Medium

Score of Parentheses

StackString

Acceptance: 63.9%

#857Hard

Minimum Cost to Hire K Workers

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 63.5%

#858Medium

Mirror Reflection

GeometryMathNumber Theory

Acceptance: 62.3%

#859Easy

Buddy Strings

Hash TableString

Acceptance: 34.0%

#860Easy

Lemonade Change

ArrayGreedy

Acceptance: 59.0%

#861Medium

Score After Flipping Matrix

ArrayBit ManipulationGreedy+1

Acceptance: 80.3%

#862Hard

Shortest Subarray with Sum at Least K

ArrayBinary SearchHeap (Priority Queue)+4

Acceptance: 32.7%

#863Medium

All Nodes Distance K in Binary Tree

Binary TreeBreadth-First SearchDepth-First Search+2

Acceptance: 68.1%

#864Hard

Shortest Path to Get All Keys

ArrayBit ManipulationBreadth-First Search+1

Acceptance: 55.0%

#865Medium

Smallest Subtree with all the Deepest Nodes

Binary TreeBreadth-First SearchDepth-First Search+2

Acceptance: 77.5%

#866Medium

Prime Palindrome

MathNumber Theory

Acceptance: 28.6%

#867Easy

Transpose Matrix

ArrayMatrixSimulation

Acceptance: 76.8%

#868Easy

Binary Gap

Bit Manipulation

Acceptance: 74.2%

#869Medium

Reordered Power of 2

CountingEnumerationHash Table+2

Acceptance: 66.0%

#870Medium

Advantage Shuffle

ArrayGreedySorting+1

Acceptance: 55.0%

#871Hard

Minimum Number of Refueling Stops

ArrayDynamic ProgrammingGreedy+1

Acceptance: 41.8%

#872Easy

Leaf-Similar Trees

Binary TreeDepth-First SearchTree

Acceptance: 70.0%

#873Medium

Length of Longest Fibonacci Subsequence

ArrayDynamic ProgrammingHash Table

Acceptance: 57.5%

#874Medium

Walking Robot Simulation

ArrayHash TableSimulation

Acceptance: 64.5%

#875Medium

Koko Eating Bananas

ArrayBinary Search

Acceptance: 50.4%

#876Easy

Middle of the Linked List

Linked ListTwo Pointers

Acceptance: 82.3%

#877Medium

Stone Game

ArrayDynamic ProgrammingGame Theory+1

Acceptance: 77.0%

#878Hard

Nth Magical Number

Binary SearchMath

Acceptance: 37.1%

#879Hard

Profitable Schemes

ArrayDynamic Programming

Acceptance: 48.1%

#880Medium

Decoded String at Index

StackString

Acceptance: 37.3%

#881Medium

Boats to Save People

ArrayGreedySorting+1

Acceptance: 62.1%

#882Hard

Reachable Nodes In Subdivided Graph

GraphHeap (Priority Queue)Shortest Path

Acceptance: 52.5%

#883Easy

Projection Area of 3D Shapes

ArrayGeometryMath+1

Acceptance: 76.3%

#884Easy

Uncommon Words from Two Sentences

CountingHash TableString

Acceptance: 75.8%

#885Medium

Spiral Matrix III

ArrayMatrixSimulation

Acceptance: 84.6%

#886Medium

Possible Bipartition

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 53.0%

#887Hard

Super Egg Drop

Binary SearchDynamic ProgrammingMath

Acceptance: 30.6%

#888Easy

Fair Candy Swap

ArrayBinary SearchHash Table+1

Acceptance: 65.3%

#889Medium

Construct Binary Tree from Preorder and Postorder Traversal

ArrayBinary TreeDivide and Conquer+2

Acceptance: 78.0%

#890Medium

Find and Replace Pattern

ArrayHash TableString

Acceptance: 76.8%

#891Hard

Sum of Subsequence Widths

ArrayMathSorting

Acceptance: 41.1%

#892Easy

Surface Area of 3D Shapes

ArrayGeometryMath+1

Acceptance: 71.2%

#893Medium

Groups of Special-Equivalent Strings

ArrayHash TableSorting+1

Acceptance: 73.5%

#894Medium

All Possible Full Binary Trees

Binary TreeDynamic ProgrammingMemoization+2

Acceptance: 82.8%

#895Hard

Maximum Frequency Stack

DesignHash TableOrdered Set+1

Acceptance: 67.1%

#896Easy

Monotonic Array

Array

Acceptance: 62.3%

#897Easy

Increasing Order Search Tree

Binary Search TreeBinary TreeDepth-First Search+2

Acceptance: 79.1%

#898Medium

Bitwise ORs of Subarrays

ArrayBit ManipulationDynamic Programming

Acceptance: 56.8%

#899Hard

Orderly Queue

MathSortingString

Acceptance: 66.8%

#900Medium

RLE Iterator

ArrayCountingDesign+1

Acceptance: 59.6%

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