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Problems Contests

Practice coding problems

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Practice coding problems

Data structures and algorithms problems in Python and Java. Read any problem for free; sign in to run and submit your code.

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56 problems

ProblemDifficultyTopicsTime

Squares of a Sorted Array
Easy20 min
- Two Pointers

Third Maximum NumberEasy20 min

Selection Algorithms

Rotate ArrayMedium20 min

Array Techniques

Find Pivot IndexEasy20 min

Prefix Sums and Difference Arrays

Container With Most WaterMedium20 min

Two Pointers

Maximum SubarrayMedium20 min

Dynamic Programming

Merge IntervalsMedium20 min

Scheduling and Intervals

Find the Duplicate NumberMedium20 min

Find the Maximum Element in an ArrayEasy15 min

Arrays and Strings

Find the Minimum Element in an ArrayEasy15 min

Arrays and Strings

Calculate the Sum of Array ElementsEasy15 min

Arrays and Strings

Find the First Occurrence of a TargetEasy15 min

Arrays and Strings

Reverse an ArrayEasy15 min

Arrays and Strings

Count Even Numbers in an ArrayEasy15 min

Arrays and Strings

Find the Second Largest Distinct ElementEasy15 min

Arrays and Strings

Rotate an Array to the RightEasy15 min

Array Techniques

Move All Zeroes to the EndEasy15 min

Two Pointers

Check Whether an Array Is SortedEasy15 min

Arrays and Strings

Check Whether a Number Is EvenFoundationalEasy15 min

Programming Fundamentals

Find the Largest of Three IntegersFoundationalEasy15 min

Programming Fundamentals

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