#include<iostream>
#include<stdio.h>
#include<string.h>
int Fa[1005];
int FindFa(int a)
{
int x = a;
while(Fa[x] != x)
{
x = Fa[x];
}
int s = x, j;
while(a != s)
{
j = Fa[a];
Fa[a] = s;
a = j;
}
return x;
}
int main()
{
int t, i, j, a, b, n, m;
scanf("%d", &t);
while(t--)
{
scanf("%d %d", &n, &m);
for(i = 1; i <= n; i++)
Fa[i] = i;
for(j = 0; j < m; j++)
{
scanf("%d %d", &a, &b);
int FA = FindFa(a);
int FB = FindFa(b);
if(FA != FB)
Fa[FA] = FB;
}
int sum = 0;
for(i = 1; i <= n; i++)
{
if(Fa[i] == i)
{
sum++;
}
}
printf("%d\n", sum);
}
return 0;
}