dsa/graphs/misc/ | desc: cycle in undirected graph

cycle detection undirected.cpp

#include <bits/stdc++.h>
using namespace std;

/* Using DFS to find a cycle in undirected graph */

int N;
vector<vector<int>> gph;
vector<bool> vis(N, false);

bool dfs(int src, int par, vector<bool>& vis){
  vis[src] = true;
  for(auto v : gph[src]) {
    if(!vis[v]){
      if(dfs(v, src, vis)) return true;
    } else if(v != par) return true;
  }
  return false;
}

// dfs(0, vis);