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
1561. Maximum Number of Coins You Can Get	Medium	84.9%	Array Game Theory+3	Read
1562. Find Latest Group of Size M	Medium	43.8%	Array Binary Search+2	Read
1564. Put Boxes Into the Warehouse I	Medium	67.9%	Array Greedy+1	Read
1567. Maximum Length of Subarray With Positive Product	Medium	44.3%	Array Dynamic Programming+1	Read
1570. Dot Product of Two Sparse Vectors	Medium	89.9%	Array Design+2	Read
1573. Number of Ways to Split a String	Medium	34.6%	Math String	Read
1574. Shortest Subarray to be Removed to Make Array Sorted	Medium	51.2%	Array Binary Search+3	Read
1577. Number of Ways Where Square of Number Is Equal to Product of Two Numbers	Medium	43.9%	Array Hash Table+2	Read
1578. Minimum Time to Make Rope Colorful	Medium	65.2%	Array Dynamic Programming+2	Read
1580. Put Boxes Into the Warehouse II	Medium	66.6%	Array Greedy+1	Read
1583. Count Unhappy Friends	Medium	62.6%	Array Simulation	Read
1584. Min Cost to Connect All Points	Medium	71.7%	Array Graph+2	Read
1586. Binary Search Tree Iterator II	Medium	63.4%	Binary Search Tree Binary Tree+4	Read
1589. Maximum Sum Obtained of Any Permutation	Medium	41.1%	Array Greedy+2	Read
1590. Make Sum Divisible by P	Medium	42.6%	Array Hash Table+1	Read
1593. Split a String Into the Max Number of Unique Substrings	Medium	68.8%	Backtracking Hash Table+1	Read
1594. Maximum Non Negative Product in a Matrix	Medium	51.5%	Array Dynamic Programming+1	Read
1596. The Most Frequently Ordered Products for Each Customer	Medium	78.3%	Database	Read
1599. Maximum Profit of Operating a Centennial Wheel	Medium	44.6%	Array Simulation	Read
1600. Throne Inheritance	Medium	68.2%	Depth-First Search Design+2	Read
1602. Find Nearest Right Node in Binary Tree	Medium	75.2%	Binary Tree Breadth-First Search+1	Read
1604. Alert Using Same Key-Card Three or More Times in a One Hour Period	Medium	46.0%	Array Hash Table+2	Read
1605. Find Valid Matrix Given Row and Column Sums	Medium	83.0%	Array Greedy+1	Read
1609. Even Odd Tree	Medium	67.1%	Binary Tree Breadth-First Search+1	Read
1612. Check If Two Expression Trees are Equivalent	Medium	71.8%	Binary Tree Counting+3	Read
1613. Find the Missing IDs	Medium	73.0%	Database	Read
1615. Maximal Network Rank	Medium	65.9%	Graph	Read
1616. Split Two Strings to Make Palindrome	Medium	32.8%	String Two Pointers	Read
1618. Maximum Font to Fit a Sentence in a Screen	Medium	62.0%	Array Binary Search+2	Read
1620. Coordinate With Maximum Network Quality	Medium	40.0%	Array Enumeration	Read
1621. Number of Sets of K Non-Overlapping Line Segments	Medium	69.3%	Combinatorics Dynamic Programming+1	Read
1625. Lexicographically Smallest String After Applying Operations	Medium	79.4%	Breadth-First Search Depth-First Search+2	Read
1626. Best Team With No Conflicts	Medium	50.9%	Array Dynamic Programming+1	Read
1628. Design an Expression Tree With Evaluate Function	Medium	82.4%	Array Binary Tree+4	Read
1630. Arithmetic Subarrays	Medium	83.7%	Array Hash Table+1	Read
1631. Path With Minimum Effort	Medium	64.1%	Array Binary Search+5	Read
1634. Add Two Polynomials Represented as Linked Lists	Medium	61.1%	Linked List Math+1	Read
1638. Count Substrings That Differ by One Character	Medium	72.4%	Dynamic Programming Enumeration+2	Read
1641. Count Sorted Vowel Strings	Medium	79.2%	Combinatorics Dynamic Programming+1	Read
1642. Furthest Building You Can Reach	Medium	50.8%	Array Greedy+1	Read
1644. Lowest Common Ancestor of a Binary Tree II	Medium	69.6%	Binary Tree Depth-First Search+1	Read
1647. Minimum Deletions to Make Character Frequencies Unique	Medium	61.3%	Greedy Hash Table+2	Read
1648. Sell Diminishing-Valued Colored Balls	Medium	29.9%	Array Binary Search+4	Read
1650. Lowest Common Ancestor of a Binary Tree III	Medium	83.0%	Binary Tree Hash Table+2	Read
1653. Minimum Deletions to Make String Balanced	Medium	68.2%	Dynamic Programming Stack+1	Read
1654. Minimum Jumps to Reach Home	Medium	30.7%	Array Breadth-First Search+1	Read
1657. Determine if Two Strings Are Close	Medium	54.2%	Counting Hash Table+2	Read
1658. Minimum Operations to Reduce X to Zero	Medium	40.5%	Array Binary Search+3	Read
1660. Correct a Binary Tree	Medium	74.3%	Binary Tree Breadth-First Search+3	Read
1663. Smallest String With A Given Numeric Value	Medium	67.5%	Greedy String	Read

#1561Medium

Maximum Number of Coins You Can Get

ArrayGame TheoryGreedy+2

Acceptance: 84.9%

#1562Medium

Find Latest Group of Size M

ArrayBinary SearchHash Table+1

Acceptance: 43.8%

#1564Medium

Put Boxes Into the Warehouse I

ArrayGreedySorting

Acceptance: 67.9%

#1567Medium

Maximum Length of Subarray With Positive Product

ArrayDynamic ProgrammingGreedy

Acceptance: 44.3%

#1570Medium

Dot Product of Two Sparse Vectors

ArrayDesignHash Table+1

Acceptance: 89.9%

#1573Medium

Number of Ways to Split a String

MathString

Acceptance: 34.6%

#1574Medium

Shortest Subarray to be Removed to Make Array Sorted

ArrayBinary SearchMonotonic Stack+2

Acceptance: 51.2%

#1577Medium

Number of Ways Where Square of Number Is Equal to Product of Two Numbers

ArrayHash TableMath+1

Acceptance: 43.9%

#1578Medium

Minimum Time to Make Rope Colorful

ArrayDynamic ProgrammingGreedy+1

Acceptance: 65.2%

#1580Medium

Put Boxes Into the Warehouse II

ArrayGreedySorting

Acceptance: 66.6%

#1583Medium

Count Unhappy Friends

ArraySimulation

Acceptance: 62.6%

#1584Medium

Min Cost to Connect All Points

ArrayGraphMinimum Spanning Tree+1

Acceptance: 71.7%

#1586Medium

Binary Search Tree Iterator II

Binary Search TreeBinary TreeDesign+3

Acceptance: 63.4%

#1589Medium

Maximum Sum Obtained of Any Permutation

ArrayGreedyPrefix Sum+1

Acceptance: 41.1%

#1590Medium

Make Sum Divisible by P

ArrayHash TablePrefix Sum

Acceptance: 42.6%

#1593Medium

Split a String Into the Max Number of Unique Substrings

BacktrackingHash TableString

Acceptance: 68.8%

#1594Medium

Maximum Non Negative Product in a Matrix

ArrayDynamic ProgrammingMatrix

Acceptance: 51.5%

#1596Medium

The Most Frequently Ordered Products for Each Customer

Database

Acceptance: 78.3%

#1599Medium

Maximum Profit of Operating a Centennial Wheel

ArraySimulation

Acceptance: 44.6%

#1600Medium

Throne Inheritance

Depth-First SearchDesignHash Table+1

Acceptance: 68.2%

#1602Medium

Find Nearest Right Node in Binary Tree

Binary TreeBreadth-First SearchTree

Acceptance: 75.2%

#1604Medium

Alert Using Same Key-Card Three or More Times in a One Hour Period

ArrayHash TableSorting+1

Acceptance: 46.0%

#1605Medium

Find Valid Matrix Given Row and Column Sums

ArrayGreedyMatrix

Acceptance: 83.0%

#1609Medium

Even Odd Tree

Binary TreeBreadth-First SearchTree

Acceptance: 67.1%

#1612Medium

Check If Two Expression Trees are Equivalent

Binary TreeCountingDepth-First Search+2

Acceptance: 71.8%

#1613Medium

Find the Missing IDs

Database

Acceptance: 73.0%

#1615Medium

Maximal Network Rank

Graph

Acceptance: 65.9%

#1616Medium

Split Two Strings to Make Palindrome

StringTwo Pointers

Acceptance: 32.8%

#1618Medium

Maximum Font to Fit a Sentence in a Screen

ArrayBinary SearchInteractive+1

Acceptance: 62.0%

#1620Medium

Coordinate With Maximum Network Quality

ArrayEnumeration

Acceptance: 40.0%

#1621Medium

Number of Sets of K Non-Overlapping Line Segments

CombinatoricsDynamic ProgrammingMath

Acceptance: 69.3%

#1625Medium

Lexicographically Smallest String After Applying Operations

Breadth-First SearchDepth-First SearchEnumeration+1

Acceptance: 79.4%

#1626Medium

Best Team With No Conflicts

ArrayDynamic ProgrammingSorting

Acceptance: 50.9%

#1628Medium

Design an Expression Tree With Evaluate Function

ArrayBinary TreeDesign+3

Acceptance: 82.4%

#1630Medium

Arithmetic Subarrays

ArrayHash TableSorting

Acceptance: 83.7%

#1631Medium

Path With Minimum Effort

ArrayBinary SearchBreadth-First Search+4

Acceptance: 64.1%

#1634Medium

Add Two Polynomials Represented as Linked Lists

Linked ListMathTwo Pointers

Acceptance: 61.1%

#1638Medium

Count Substrings That Differ by One Character

Dynamic ProgrammingEnumerationHash Table+1

Acceptance: 72.4%

#1641Medium

Count Sorted Vowel Strings

CombinatoricsDynamic ProgrammingMath

Acceptance: 79.2%

#1642Medium

Furthest Building You Can Reach

ArrayGreedyHeap (Priority Queue)

Acceptance: 50.8%

#1644Medium

Lowest Common Ancestor of a Binary Tree II

Binary TreeDepth-First SearchTree

Acceptance: 69.6%

#1647Medium

Minimum Deletions to Make Character Frequencies Unique

GreedyHash TableSorting+1

Acceptance: 61.3%

#1648Medium

Sell Diminishing-Valued Colored Balls

ArrayBinary SearchGreedy+3

Acceptance: 29.9%

#1650Medium

Lowest Common Ancestor of a Binary Tree III

Binary TreeHash TableTree+1

Acceptance: 83.0%

#1653Medium

Minimum Deletions to Make String Balanced

Dynamic ProgrammingStackString

Acceptance: 68.2%

#1654Medium

Minimum Jumps to Reach Home

ArrayBreadth-First SearchDynamic Programming

Acceptance: 30.7%

#1657Medium

Determine if Two Strings Are Close

CountingHash TableSorting+1

Acceptance: 54.2%

#1658Medium

Minimum Operations to Reduce X to Zero

ArrayBinary SearchHash Table+2

Acceptance: 40.5%

#1660Medium

Correct a Binary Tree

Binary TreeBreadth-First SearchDepth-First Search+2

Acceptance: 74.3%

#1663Medium

Smallest String With A Given Numeric Value

GreedyString

Acceptance: 67.5%

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Master DSA with Step-by-Step Solutions

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