Graph Valid Tree
Detailed guide and Python implementation for the 'Graph Valid Tree' problem.
Problem Statement
You have a graph of n nodes labeled from 0 to n - 1. You are given an integer n and a list of edges where edges[i] = [ai, bi] indicates that there is an undirected edge between nodes ai and bi in the graph.
Return True if the edges of the given graph make up a valid tree, and False otherwise.
Write a function validTree(n: int, edges: List[List[int]]) -> bool.
- •1 <= n <= 2000
- •0 <= len(edges) <= 5000
- •edges[i].length == 2
- •0 <= ai, bi < n
Examples
n = 5, edges = [[0,1],[0,2],[0,3],[1,4]]
True
The graph is fully connected and contains no cycles, so it is a valid tree.
n = 5, edges = [[0,1],[1,2],[2,3],[1,3],[1,4]]
False
The graph contains a cycle 1-2-3-1, so it is not a valid tree.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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