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Python Coding
Challenges

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925 challenges 556 easy 323 medium 46 hard

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All Python Basics Strings & Text Lists & Arrays Dicts & Sets Functions & Closures OOP & Classes Data Structures & Algorithms Advanced Python Iterators & Generators Decorators & Context Managers Error Handling & Exceptions Regular Expressions Math & Number Theory Bit Manipulation Dynamic Programming Trees & Binary Trees Graphs & Graph Algorithms Recursion & Backtracking Greedy Algorithms Binary Search Two Pointers & Sliding Window Stacks & Queues Heaps & Priority Queues Linked Lists Matrix & 2D Arrays Datetime & Time Calculations Data Formats & Parsing SQL & SQLite Numpy & Vectorized Computing Cryptography & Hashing

Graphs & Graph Algorithms medium

Hamiltonian Path Check

Implement a function that checks whether an undirected graph has a Hamiltonian path using DFS and backtracking.

graph dfs backtracking

Graphs & Graph Algorithms medium

All Paths from Source to Target

Given a directed acyclic graph, return all paths from node 0 to the last node.

graph dfs backtracking

Graphs & Graph Algorithms medium

Graph Coloring Backtrack

Given an adjacency list and a number of colors, decide if the graph can be colored so no adjacent vertices share a color.

backtracking graphs coloring

Graphs & Graph Algorithms medium

Android unlock patterns

Count the number of valid Android unlock patterns of a given length using a 3x3 grid with adjacency constraints.

graphs dfs backtracking

Showing 1–4 of 4 challenges · Graphs & Graph Algorithms

Graphs & Graph Algorithms — Python coding challenges

What you will find here

This page lists graphs & graph 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.