Articulation Points
Implement a function that returns the articulation points of an undirected graph.
Bridges in Graph
Implement a function that returns all bridges in an undirected graph.
Hamiltonian Path Check
Implement a function that checks whether an undirected graph has a Hamiltonian path using DFS and backtracking.
Course Schedule Can Finish
Given numCourses and prerequisites, return whether all courses can be finished without cyclic dependencies.
Graph Valid Tree
Determine if n nodes and an edge list form a valid tree (connected and acyclic).
All Paths from Source to Target
Given a directed acyclic graph, return all paths from node 0 to the last node.
Topological Sort via DFS
Return a deterministic topological ordering of nodes in a directed acyclic graph using DFS, or an empty list if a cycle exists.
Strongly Connected Components (Kosaraju's Algorithm)
Implement a function to find strongly connected components in a directed graph using Kosaraju's algorithm.
Surrounded Regions
Given an M×N grid of 'X' and 'O', capture all regions of 'O' that are completely surrounded by 'X'.
Possible bipartition
Given N people and a list of mutual dislikes, check if they can be divided into two groups with no dislike inside a group.
Android unlock patterns
Count the number of valid Android unlock patterns of a given length using a 3x3 grid with adjacency constraints.
Most stones removed
Given stone coordinates on a grid, find the maximum number of stones that can be removed while every stone shares a row or column with another remaining stone.
Showing 1–12 of 12 challenges · medium · Graphs & Graph Algorithms
Graphs & Graph Algorithms — Python coding challenges
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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.
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