#include <bits/stdc++.h>
using namespace std;

// subtask 1

int main() {
    int T;
    cin >> T;
    while (T--) {
        int N, M;
        cin >> N >> M;
        vector<int> A(M), B(M);
        for (int i = 0; i < M; i++) {
            cin >> A[i] >> B[i];
        }
        assert(M == 1 || M == N);
        cout << "Yes" << endl;
    }
    return 0;
}