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Python Coding Challenges

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467 challenges 330 easy 120 medium 17 hard
Data Structures & Algorithms easy

Index of peak element

Implement a function that returns the index of any peak element in a given integer array.

arrays search peak
+10 pts 15m
Data Structures & Algorithms easy

Count pairs with given difference

Count how many unordered pairs in a list have a given absolute difference using an efficient approach.

hash map counting arrays
+12 pts 15m
Data Structures & Algorithms medium

Find Peak Element

Implement a function that returns the index of any peak element in an integer array.

arrays search binary-search
+20 pts 25m
Data Structures & Algorithms easy

Previous Smaller Element

Find the nearest previous index with a smaller value for every element in an array.

arrays stack monotonic-stack
+10 pts 15m
Data Structures & Algorithms medium

Longest Consecutive Sequence

Given an unsorted list of integers, find the length of the longest consecutive elements sequence in O(n) time.

hash set array linear
+20 pts 20m
Data Structures & Algorithms hard

Median of Two Sorted Arrays

Given two sorted arrays, return the median of the combined sorted array in O(log(min(n,m))) time.

median binary search arrays
+45 pts 40m
Data Structures & Algorithms easy

Pascal Triangle Row

Given a non-negative integer n, return the nth row of Pascal's triangle as a list of integers.

math combinatorics arrays
+10 pts 15m
Data Structures & Algorithms easy

Bubble Sort

Implement bubble sort that sorts a list of numbers in ascending order.

sorting arrays algorithms
+8 pts 12m
Data Structures & Algorithms easy

Exponential Search

Implement exponential search to find any valid index of a target in a sorted list.

searching sorted-array algorithms
+10 pts 15m

Showing 9 challenges · Data Structures & Algorithms

Data Structures & Algorithms — Python coding challenges

What you will find here

This page lists data structures & algorithms challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

Challenges vs tutorials and quizzes

Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.