Cycle Detection
Detailed guide and Python implementation for the 'Cycle Detection' problem.
Problem Statement
Write a function has_cycle(graph) that takes a directed graph represented as an adjacency list of neighbor lists and returns True if it contains at least one cycle, or False otherwise.
- •1 <= V <= 500
- •0 <= E <= 1000
Examples
graph = {0: [1], 1: [2], 2: [0]}True
The path 0 -> 1 -> 2 -> 0 forms a cycle.
graph = {0: [1], 1: [2], 2: []}False
The graph is acyclic.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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