Min of three numbers
Write a function that returns the minimum of three integers.
Find Minimum Value
Write a function that returns the minimum integer from a given list.
Coin change (DP)
Find the minimum number of coins to make exactly the target amount.
Min cost climbing stairs
Compute the minimum total cost to reach the top of a staircase, given you can climb 1 or 2 steps at a time.
Triangle Minimum Path
Compute the minimum path sum from top to bottom of a triangle given as a list of lists.
Edit Distance (Levenshtein Distance)
Implement the classic edit distance algorithm to find the minimum number of single-character edits required to transform one string into another.
Coin Change Minimum
Given coin denominations and a target amount, compute the minimum number of coins needed or -1 if impossible.
Palindrome Partitioning Minimum Cuts
Given a string, return the minimum number of cuts needed such that every substring in the partition is a palindrome.
Egg Drop Puzzle
Given k eggs and n floors, compute the minimum number of attempts required in the worst case to find the highest safe floor.
Paint House Colors
Given a cost matrix, compute the minimum total cost to paint all houses with no two adjacent houses having the same color.
Minimum Depth of Tree
Given a binary tree, compute the minimum depth from the root to the nearest leaf node.
Minimum Cut
Given an undirected graph in adjacency-list form, return the size of the minimum edge cut that disconnects the graph.
Network Delay Time
Given a directed weighted graph and a starting node, find the minimum time for a signal to reach all nodes, or -1 if unreachable.
Best Time to Buy and Sell Stock
Given a list of daily stock prices, determine the maximum profit achievable by buying on one day and selling on a later day.
Minimum Window Substring
Implement a sliding window algorithm to find the minimum window substring containing all characters of a given pattern.
Rotting Oranges Time
Given a grid of fresh, rotten, and empty cells, compute the minimum minutes until all fresh oranges rot, or -1 if some are unreachable.
Showing 16 challenges
Guide: free Python coding challenges
Practice Python by solving problems
PythonSkillset challenges are hands-on coding exercises from beginner to advanced. Open a challenge, read the problem, write Python in the split-pane editor, and run tests with Pyodide — no install required.
How to use the arena
- Pick a category — basics, algorithms, strings, and more
- Open a challenge, read the statement, and edit the starter code
- Run tests, fix failures, then try a related quiz or tutorial lesson
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.