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.
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.
Crawler Log Folder
Given a list of folder navigation operations, compute the minimum steps required to return to the main folder.
Longest Harmonious Subsequence
Given a list of integers, find the length of the longest harmonious subsequence where the difference between maximum and minimum values is exactly 1.
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 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.
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.
Swim in Rising Water
Find the minimum time needed to swim from the top-left to the bottom-right of a grid where water level rises and you can only move to cells with elevation ≤ current time.
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.
Showing 1–24 of 53 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.