// timer should be cleared with 0 each test
// cc should be cleared by zero
// clear the adjacency list
//
vector < int > v[MX];
int low[MX] , timer[MX] , in[MX] , cc;
stack < int > S;
int T , Tn , comp , scc[MX];
void dfs(int x){
    low[x] = timer[x] = ++cc;
    S.push(x); in[x] = 1;
    for(int j=0;j<v[x].size();j++){
        int nxt = v[x][j];
        if(timer[nxt] == 0){
            dfs(nxt);
            low[x] = min(low[x] , low[nxt]);
        }
        else {
            if(in[nxt])
                low[x] = min(low[x] , timer[nxt]);
            }
    }
    if(low[x] == timer[x]){
        ++comp;
        while(1){
            int node = S.top();
            in[node] = 0; S.pop();
            scc[node] = comp;
            if(node == x) break;
        }
    }
}