#include <stdio.h>
int father[1010];

int find(int a)
{
    int k, j, r;
    r = a ;
    while(r != father[r])
    r = father[r];
    k = a;
    while(k != r)
    {
        j = father[k];
        father[k] = r;
        k = j;
    }
    return r;
} 
/*int find(int a)
{
    while(father[a] != a)
    father[a] = find(father[a]);
    return father[a];
} */
void mercy(int a, int b)
{
    int p = find(a);
    int q = find(b);
    if(p != q)
    father[p] = q;
}

int main()
{
    int i, t; 
    scanf("%d", &t);
    while(t--)
    {
        int n, m, a, b;
        scanf("%d %d", &n, &m);
        for(i=1; i<=n; i++)
        father[i] = i;
        for(i=0; i<m; i++)
        {
            scanf("%d %d", &a, &b);
            mercy(a, b);
        }
        //printf("\n");
        int total = 0;
        for(i=1; i<=n; i++)
        {
            if(father[i] == i)
            total++;
        }
        printf("%d\n", total);
    }
    return 0;
}