Consider a graph with num nodes, labeled from 0 to num - 1. Given num and a list of edges where each edges[i] = [a, b] represents an undirected connection between nodes a and b, determine whether the provided edges form a valid tree.
A valid tree is a connected, acyclic graph that spans all num nodes. This means:
num - 1 edges, where num is the number of nodesReturn true if the edges form a valid tree; otherwise, return false.
num: number: Number of nodes in the graphedges: Array<[number, number]>: A 2D array where edges[i] = [a, b] represents an undirected edge between nodes a and bInput: num = 5, edges = [[3,4],[0,3],[1,2],[0,1]]Output: trueExplanation: The graph consists of 5 nodes (0, 1, 2, 3, 4) connected by 4 edges. All nodes are reachable from any other node, and there are no cycles. The graph has exactly num - 1 = 4 edges, satisfying the conditions for a valid tree.
Input: num = 5, edges = [[0,1],[1,2],[2,3],[3,4],[1,4]]Output: falseExplanation: Although all nodes are connected, the graph contains a cycle (e.g., 1 -> 4 -> 3 -> 1), which violates the condition of being acyclic. Hence, the graph is not a valid tree.
Input: num = 3, edges = [[0,1]]Output: falseExplanation: The graph consists of 3 nodes (0, 1, 2), but only 1 edge is provided. This leaves node 2 disconnected, violating the condition of being connected. Hence, the graph is not a valid tree.
num <= 1000edges.length <= 1000edges[i].length == 2a, b < numa != bConsider a graph with num nodes, labeled from 0 to num - 1. Given num and a list of edges where each edges[i] = [a, b] represents an undirected connection between nodes a and b, determine whether the provided edges form a valid tree.
A valid tree is a connected, acyclic graph that spans all num nodes. This means:
num - 1 edges, where num is the number of nodesReturn true if the edges form a valid tree; otherwise, return false.
num: number: Number of nodes in the graphedges: Array<[number, number]>: A 2D array where edges[i] = [a, b] represents an undirected edge between nodes a and bInput: num = 5, edges = [[3,4],[0,3],[1,2],[0,1]]Output: trueExplanation: The graph consists of 5 nodes (0, 1, 2, 3, 4) connected by 4 edges. All nodes are reachable from any other node, and there are no cycles. The graph has exactly num - 1 = 4 edges, satisfying the conditions for a valid tree.
Input: num = 5, edges = [[0,1],[1,2],[2,3],[3,4],[1,4]]Output: falseExplanation: Although all nodes are connected, the graph contains a cycle (e.g., 1 -> 4 -> 3 -> 1), which violates the condition of being acyclic. Hence, the graph is not a valid tree.
Input: num = 3, edges = [[0,1]]Output: falseExplanation: The graph consists of 3 nodes (0, 1, 2), but only 1 edge is provided. This leaves node 2 disconnected, violating the condition of being connected. Hence, the graph is not a valid tree.
num <= 1000edges.length <= 1000edges[i].length == 2a, b < numa != bconsole.log() statements will appear here.