Jump Game Minimum Jumps
Given an array of non-negative integers where each element is the maximum jump length, compute the minimum jumps to reach the last index.
Minimum Remove Valid Parentheses
Given a string with parentheses and letters, remove the fewest parentheses to make it valid.
Coin change (DP)
Find the minimum number of coins to make exactly the target amount.
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.
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 Falling Path Sum
Compute the minimum falling path sum in an n x n matrix by moving down or diagonally each step.
Matrix Chain Multiplication
Given a list of matrix dimensions, compute the minimum multiplication cost using dynamic programming.
Minimum Path Sum Matrix
Implement a function that computes the minimum path sum from the top-left to the bottom-right of a grid moving only right or down.
Dungeon Game Minimum Health
Compute the minimum initial health needed to reach the bottom-right corner of a dungeon grid without health dropping to zero or below.
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.
Prim's Minimum Spanning Tree
Given a connected undirected weighted graph, compute the total weight of its minimum spanning tree using Prim's algorithm.
Kruskal MST
Implement Kruskal's algorithm to compute the total weight of a minimum spanning tree in a connected undirected graph.
Minimum Height Trees
Given an undirected tree, find all root nodes that minimize the height of the tree.
Open the Lock BFS
Implement a BFS solution to find the minimum number of turns needed to open a 4-wheel lock, avoiding a set of deadends.
Minimum Genetic Mutation
Implement a function to compute the minimum number of single-character mutations needed to transform one gene string into another, using a given bank of valid mutations.
Candy Distribution
Compute the minimum total candies needed so that every child gets at least one and children with higher ratings than neighbors get more candies.
Meeting Rooms Minimum
Given a list of meeting time intervals, compute the minimum number of conference rooms required.
Boats to Save People
Given a list of people weights and a boat's weight limit, return the minimum number of boats required.
Minimum Number of Arrows to Burst Balloons
Given balloon intervals, find the minimum number of arrows to burst all balloons by merging overlaps.
Painter Partition Problem
Given board lengths and k painters, find the minimum possible maximum total length a painter must paint.
Non-overlapping Intervals
Given a list of intervals, return the minimum number of intervals to remove to make the rest non-overlapping.
Find Minimum in Rotated Sorted Array
Implement a function that finds the minimum element in a rotated sorted array of distinct integers in O(log n) time.
Koko Eating Bananas
Given piles of bananas and hours, find the minimum integer eating speed Koko needs to finish all piles within H hours.
Showing 1–24 of 35 challenges · medium
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.