Python coding challenges: "edges"

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Data Structures & Algorithms medium

Redundant Connection

Given a list of edges forming a tree plus one extra edge, return the edge that appears last in the input and creates a cycle.

graphs union-find cycle-detection

+25 pts 25m

Graphs & Graph Algorithms medium

Bellman-Ford Algorithm

Implement the Bellman-Ford algorithm to compute shortest distances from a source in a directed weighted graph with up to 100 vertices and negative edges.

shortest-path negative-edges graph

+30 pts 30m

Showing 2 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.

Python Coding Challenges