Code Challenges

Get better at coding with practice problems.

Coding Challenges

Select a problem, write code, run test cases, and submit your solution.

Start with beginner challenges

Array Sorting Two Pointers

Learner

Implement the `findPairWithSortedSum` method that checks whether a sorted array contains a pair with the required sum.

Intermediate

Implement the `kthSmallestValue` method that returns the kth smallest value from the array.

Array Hash Map Counting Sorting

Intermediate

Implement the `sortByFrequencyAscending` method that sorts values by increasing frequency while resolving ties consistently.

Intermediate

Implement the `sortArrayByAbsoluteValue` method that returns the array sorted according to absolute value.

Array Linear Search Sorting

Learner

Implement the `findSmallestMissingPositiveSorted` method that finds the smallest positive integer missing from a sorted array.

Array Decision Making Sorting

Intermediate

Implement the `sortOnlyEvenNumbers` method that sorts only the even numbers while keeping odd numbers in their positions.

Loop Array Sorting

Learner

Implement the `insertionSortArray` method that returns the array after sorting it using insertion sort logic.

Loop Array Sorting

Learner

Implement the `bubbleSortArray` method that returns the array after sorting it using bubble sort logic.

Loop Array Sorting

Learner

Implement the `selectionSortArray` method that returns the array after sorting it using selection sort logic.

Loop Array Sorting

Learner

Implement the `isArraySortedAscending` method that checks whether the array is sorted in ascending order.

Array Sorting Two Pointers

Learner

Implement the `mergeTwoSortedArrays` method that merges two sorted arrays into one sorted result array.

Array Sorting Binary Search

Learner

Implement the method `firstOccurrence` that returns the first index of a target value in a sorted array.