package main

import . "fmt"
import . "os"
import bf "bufio"

func main() {
	rd:=bf.NewReader(Stdin)
	var t int
	Fscan(rd,&t)
	for ;t>0;t-- {
		var n,m int
		Fscan(rd,&n,&m)
		for ;m>0;m-- {
			var u,v int
			Fscan(rd,&u,&v)
		}
		if n==1 {
			Println("No")
		} else {
			Println("Yes")
		}
	}
}