Code Challenges

Code Challenges

Practice your coding skills with these interactive challenges. Write code, run tests, and get instant feedback.

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All Challenges

Sum of Array
Write a function called `sum_array` that takes a list of numbers and returns the sum of all elements...
Easy
FizzBuzz
Write a function called `fizz_buzz` that takes a number n and returns a list of strings from 1 to n....
Easy
Palindrome Checker
Write a function called `is_palindrome` that takes a string and returns True if it's a palindrome (r...
Medium
Find Duplicates
Write a function called `find_duplicates` that takes a list and returns a new list containing only t...
Medium
Flatten Nested List
Write a function called `flatten` that takes a deeply nested list and returns a single flat list wit...
Hard
Two Sum
Write a function called `two_sum` that takes a list of numbers and a target sum. Return the indices ...
Medium

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