#includeusing namespace std;int solve(int &W) /*这里一定要用引用,为了赋给它值*/{ int wl, dl, wr, dr; cin >> wl >> dl >> wr >> dr; bool f1 = true, f2 = true; if(!wl) f1 = solve(wl); /*沿着这个子天平找下去*/ if(!wr) f2 = solve(wr); W = wl + wr; /*将它的重 加起来*/ return ( f1 && f2 && (wl*dl == wr*dr));}int main(){ int T, W; cin >> T; while(T--) { if(solve(W)) cout << "YES" << endl; else cout << "NO" << endl; if(T) cout << endl; } return 0;}