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| bool dfs(int u, int root, vector<vector<int>>& adj, vector<int>& seen, vector<int>& vis) {
if(seen[u] == root) return true;
if(vis[u] != -1) return false;
vis[u] = root;
seen[u] = root;
for(auto& v : adj[u]) {
if(dfs(v, root, adj, seen, vis))
return true;
}
seen[u] = -1;
return false;
}
bool cycleInGraph(vector<vector<int>> edges) {
int n = edges.size();
vector<int> seen(n, -1), vis(n, -1);
for(int i = 0; i < n; i++) {
if(vis[i] != -1) continue;
if(dfs(i,i,edges,seen, vis))
return true;
}
return false;
}
|
