#include using namespace std; int main(){ ios_base::sync_with_stdio(false); cin.tie(nullptr); int N,M; cin >> N >> M; vector> Graph(N),rev(N); for(int i=0; i> u >> v; u--; v--; Graph.at(u).push_back(v); rev.at(v).push_back(u); } vector V(N); vector already(N); vector win(N); queue Q; for(int i=0; i