//using kahn's algo 
    public boolean isCyclic(int V, ArrayList<ArrayList<Integer>> adj) {
        ans = new int[V];
        idx = 0;
        
        kahn(V , adj);
        
        return idx == V ? false : true;
    }
    static int ans[];
    static int idx ;
    public static void kahn(int v, ArrayList<ArrayList<Integer>> graph){
        
        //find indegree
        int indegree[] = new int[v];
        for(int i = 0 ;i < v ; i++){
            for(int edge : graph.get(i)){
                indegree[edge] ++;
            }
        }
        
        //add indegree 0 to q 
        Queue<Integer> q = new ArrayDeque<>();
        for(int i = 0 ;i < v ; i++){
            if(indegree[i] == 0)
            q.add(i);
        }
        
        //DAG no need of visited
        //fire BFS 
        while(q.size() > 0){
            int rem = q.remove();
            
            ans[idx] = rem;
            idx++;
            
            //reduce indegree of nbrs and add it in the q if 0
            //0 means no dependencies they can be printed
            for(int edge: graph.get(rem)){
                indegree[edge]--;
                
                if(indegree[edge] == 0)
                q.add(edge);
            }
        }
        
        
    }