#!/usr/bin/env python3
import sys

MOD = 998244353

def main():
    T = int(input())

    for i in range(T):
        N, M = map(int, input().split())
        for _ in range(M):
            u, v = map(int, input().split())
        if N == 1:
            print("No")
        else:
            print("Yes")
    return

    

if __name__ == '__main__':
    main()