#include<stdio.h>
#include<string.h>
#define N 100
int map[N][N];
int main() {
int t,n,m,i,j,k,sum1,sum2,total,mid,a,b;
scanf("%d",&t);
while(t--) {
scanf("%d%d",&n,&m);
memset(map,0,sizeof(map));
while(m--) {
scanf("%d%d",&a,&b);
map[a][b]=1;map[b][a]=-1;
}
for(k=1;k<=n;k++)
for(i=1;i<=n;i++)
for(j=1;j<=n;j++) {
if(map[i][k]==1&&map[k][j]==1)
map[i][j]=1;
if(map[i][k]==-1&&map[k][j]==-1)
map[i][j]=-1;
}
total=0;mid=(n+1)/2;
for(i=1;i<=n;i++) {
sum1=0;sum2=0;
for(j=1;j<=n;j++) {
if(map[i][j]==1)
sum1++;
if(map[i][j]==-1)
sum2++;
}
if(sum1>=mid||sum2>=mid)
total++;
}
printf("%d
",total);
}
return 0;
}