Detect cycle in an undirected graph
Medium Accuracy: 35.66% Submissions: 100k+ Points: 4

Given an undirected graph with V vertices and E edges, check whether it contains any cycle or not. 

Example 1:


Output: 1
Explanation: 1->2->3->4->1 is a cycle.

Example 2:


Output: 0
Explanation: No cycle in the graph.


Your Task:
You don't need to read or print anything. Your task is to complete the function isCycle() which takes V denoting the number of vertices and adjacency list as input parameters and returns a boolean value denoting if the undirected graph contains any cycle or not, return 1 if a cycle is present else return 0.

NOTE: The adjacency list denotes the edges of the graph where edges[i][0] and edges[i][1] represent an edge.


Expected Time Complexity: O(V + E)
Expected Space Complexity: O(V)


1 ≤ V, E ≤ 105

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Detect cycle in an undirected graph

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