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
1501. Countries You Can Safely Invest In	Medium	50.3%	Database	Read
1502. Can Make Arithmetic Progression From Sequence	Easy	68.9%	Array Sorting	Read
1503. Last Moment Before All Ants Fall Out of a Plank	Medium	68.3%	Array Brainteaser+1	Read
1504. Count Submatrices With All Ones	Medium	71.0%	Array Dynamic Programming+3	Read
1505. Minimum Possible Integer After at Most K Adjacent Swaps On Digits	Hard	41.8%	Binary Indexed Tree Greedy+2	Read
1506. Find Root of N-Ary Tree	Medium	78.4%	Bit Manipulation Depth-First Search+2	Read
1507. Reformat Date	Easy	69.0%	String	Read
1508. Range Sum of Sorted Subarray Sums	Medium	63.2%	Array Binary Search+2	Read
1509. Minimum Difference Between Largest and Smallest Value in Three Moves	Medium	59.2%	Array Greedy+1	Read
1510. Stone Game IV	Hard	65.2%	Dynamic Programming Game Theory+1	Read
1511. Customer Order Frequency	Easy	67.3%	Database	Read
1512. Number of Good Pairs	Easy	89.9%	Array Counting+2	Read
1513. Number of Substrings With Only 1s	Medium	57.4%	Math String	Read
1514. Path with Maximum Probability	Medium	65.4%	Array Graph+2	Read
1515. Best Position for a Service Centre	Hard	35.8%	Array Geometry+2	Read
1516. Move Sub-Tree of N-Ary Tree	Hard	59.7%	Depth-First Search Tree	Read
1517. Find Users With Valid E-Mails	Easy	44.0%	Database	Read
1518. Water Bottles	Easy	72.6%	Math Simulation	Read
1519. Number of Nodes in the Sub-Tree With the Same Label	Medium	55.5%	Breadth-First Search Counting+3	Read
1520. Maximum Number of Non-Overlapping Substrings	Hard	64.4%	Greedy String	Read
1521. Find a Value of a Mysterious Function Closest to Target	Hard	47.7%	Array Binary Search+2	Read
1522. Diameter of N-Ary Tree	Medium	75.4%	Depth-First Search Tree	Read
1523. Count Odd Numbers in an Interval Range	Easy	54.4%	Math	Read
1524. Number of Sub-arrays With Odd Sum	Medium	55.7%	Array Dynamic Programming+2	Read
1525. Number of Good Ways to Split a String	Medium	68.2%	Bit Manipulation Dynamic Programming+2	Read
1526. Minimum Number of Increments on Subarrays to Form a Target Array	Hard	78.2%	Array Dynamic Programming+3	Read
1527. Patients With a Condition	Easy	40.0%	Database	Read
1528. Shuffle String	Easy	85.5%	Array String	Read
1529. Minimum Suffix Flips	Medium	73.9%	Greedy String	Read
1530. Number of Good Leaf Nodes Pairs	Medium	71.9%	Binary Tree Depth-First Search+1	Read
1531. String Compression II	Hard	52.2%	Dynamic Programming String	Read
1532. The Most Recent Three Orders	Medium	68.6%	Database	Read
1533. Find the Index of the Large Integer	Medium	56.7%	Array Binary Search+1	Read
1534. Count Good Triplets	Easy	85.5%	Array Enumeration	Read
1535. Find the Winner of an Array Game	Medium	56.8%	Array Simulation	Read
1536. Minimum Swaps to Arrange a Binary Grid	Medium	70.1%	Array Greedy+1	Read
1537. Get the Maximum Score	Hard	41.5%	Array Dynamic Programming+2	Read
1538. Guess the Majority in a Hidden Array	Medium	68.8%	Array Interactive+1	Read
1539. Kth Missing Positive Number	Easy	63.9%	Array Binary Search	Read
1540. Can Convert String in K Moves	Medium	37.6%	Hash Table String	Read
1541. Minimum Insertions to Balance a Parentheses String	Medium	53.5%	Greedy Stack+1	Read
1542. Find Longest Awesome Substring	Hard	47.4%	Bit Manipulation Hash Table+1	Read
1543. Fix Product Name Format	Easy	59.1%	Database	Read
1544. Make The String Great	Easy	68.2%	Stack String	Read
1545. Find Kth Bit in Nth Binary String	Medium	73.7%	Recursion Simulation+1	Read
1546. Maximum Number of Non-Overlapping Subarrays With Sum Equals Target	Medium	49.4%	Array Greedy+2	Read
1547. Minimum Cost to Cut a Stick	Hard	62.9%	Array Dynamic Programming+1	Read
1548. The Most Similar Path in a Graph	Hard	59.2%	Dynamic Programming Graph	Read
1549. The Most Recent Orders for Each Product	Medium	64.9%	Database	Read
1550. Three Consecutive Odds	Easy	69.3%	Array	Read

#1501Medium

Countries You Can Safely Invest In

Database

Acceptance: 50.3%

#1502Easy

Can Make Arithmetic Progression From Sequence

ArraySorting

Acceptance: 68.9%

#1503Medium

Last Moment Before All Ants Fall Out of a Plank

ArrayBrainteaserSimulation

Acceptance: 68.3%

#1504Medium

Count Submatrices With All Ones

ArrayDynamic ProgrammingMatrix+2

Acceptance: 71.0%

#1505Hard

Minimum Possible Integer After at Most K Adjacent Swaps On Digits

Binary Indexed TreeGreedySegment Tree+1

Acceptance: 41.8%

#1506Medium

Find Root of N-Ary Tree

Bit ManipulationDepth-First SearchHash Table+1

Acceptance: 78.4%

#1507Easy

Reformat Date

String

Acceptance: 69.0%

#1508Medium

Range Sum of Sorted Subarray Sums

ArrayBinary SearchSorting+1

Acceptance: 63.2%

#1509Medium

Minimum Difference Between Largest and Smallest Value in Three Moves

ArrayGreedySorting

Acceptance: 59.2%

#1510Hard

Stone Game IV

Dynamic ProgrammingGame TheoryMath

Acceptance: 65.2%

#1511Easy

Customer Order Frequency

Database

Acceptance: 67.3%

#1512Easy

Number of Good Pairs

ArrayCountingHash Table+1

Acceptance: 89.9%

#1513Medium

Number of Substrings With Only 1s

MathString

Acceptance: 57.4%

#1514Medium

Path with Maximum Probability

ArrayGraphHeap (Priority Queue)+1

Acceptance: 65.4%

#1515Hard

Best Position for a Service Centre

ArrayGeometryMath+1

Acceptance: 35.8%

#1516Hard

Move Sub-Tree of N-Ary Tree

Depth-First SearchTree

Acceptance: 59.7%

#1517Easy

Find Users With Valid E-Mails

Database

Acceptance: 44.0%

#1518Easy

Water Bottles

MathSimulation

Acceptance: 72.6%

#1519Medium

Number of Nodes in the Sub-Tree With the Same Label

Breadth-First SearchCountingDepth-First Search+2

Acceptance: 55.5%

#1520Hard

Maximum Number of Non-Overlapping Substrings

GreedyString

Acceptance: 64.4%

#1521Hard

Find a Value of a Mysterious Function Closest to Target

ArrayBinary SearchBit Manipulation+1

Acceptance: 47.7%

#1522Medium

Diameter of N-Ary Tree

Depth-First SearchTree

Acceptance: 75.4%

#1523Easy

Count Odd Numbers in an Interval Range

Math

Acceptance: 54.4%

#1524Medium

Number of Sub-arrays With Odd Sum

ArrayDynamic ProgrammingMath+1

Acceptance: 55.7%

#1525Medium

Number of Good Ways to Split a String

Bit ManipulationDynamic ProgrammingHash Table+1

Acceptance: 68.2%

#1526Hard

Minimum Number of Increments on Subarrays to Form a Target Array

ArrayDynamic ProgrammingGreedy+2

Acceptance: 78.2%

#1527Easy

Patients With a Condition

Database

Acceptance: 40.0%

#1528Easy

Shuffle String

ArrayString

Acceptance: 85.5%

#1529Medium

Minimum Suffix Flips

GreedyString

Acceptance: 73.9%

#1530Medium

Number of Good Leaf Nodes Pairs

Binary TreeDepth-First SearchTree

Acceptance: 71.9%

#1531Hard

String Compression II

Dynamic ProgrammingString

Acceptance: 52.2%

#1532Medium

The Most Recent Three Orders

Database

Acceptance: 68.6%

#1533Medium

Find the Index of the Large Integer

ArrayBinary SearchInteractive

Acceptance: 56.7%

#1534Easy

Count Good Triplets

ArrayEnumeration

Acceptance: 85.5%

#1535Medium

Find the Winner of an Array Game

ArraySimulation

Acceptance: 56.8%

#1536Medium

Minimum Swaps to Arrange a Binary Grid

ArrayGreedyMatrix

Acceptance: 70.1%

#1537Hard

Get the Maximum Score

ArrayDynamic ProgrammingGreedy+1

Acceptance: 41.5%

#1538Medium

Guess the Majority in a Hidden Array

ArrayInteractiveMath

Acceptance: 68.8%

#1539Easy

Kth Missing Positive Number

ArrayBinary Search

Acceptance: 63.9%

#1540Medium

Can Convert String in K Moves

Hash TableString

Acceptance: 37.6%

#1541Medium

Minimum Insertions to Balance a Parentheses String

GreedyStackString

Acceptance: 53.5%

#1542Hard

Find Longest Awesome Substring

Bit ManipulationHash TableString

Acceptance: 47.4%

#1543Easy

Fix Product Name Format

Database

Acceptance: 59.1%

#1544Easy

Make The String Great

StackString

Acceptance: 68.2%

#1545Medium

Find Kth Bit in Nth Binary String

RecursionSimulationString

Acceptance: 73.7%

#1546Medium

Maximum Number of Non-Overlapping Subarrays With Sum Equals Target

ArrayGreedyHash Table+1

Acceptance: 49.4%

#1547Hard

Minimum Cost to Cut a Stick

ArrayDynamic ProgrammingSorting

Acceptance: 62.9%

#1548Hard

The Most Similar Path in a Graph

Dynamic ProgrammingGraph

Acceptance: 59.2%

#1549Medium

The Most Recent Orders for Each Product

Database

Acceptance: 64.9%

#1550Easy

Three Consecutive Odds

Array

Acceptance: 69.3%

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