1 #include <bits/stdc++.h>
 2 using namespace std;
 3 int pre[1001],r[1001],t,n,m;
 4 int findset(int x) {
 5     int r=x;
 6     while(pre[r]!=r) r=pre[r];
 7     int i=x,j;
 8     while(i!=r) {
 9         j=pre[i];
10         pre[i]=r;
11         i=j;
12     }
13     return r;
14 }
15 void join(int a,int b) {
16     int f1=findset(a),f2=findset(b);
17     if(r[f1]<=r[f2]) {
18         pre[f1]=f2;
19         if(r[f1]==r[f2]) r[f2]++;
20     }
21     else pre[f2]=f1;
22 }
23 int main() {
24     scanf("%d",&t);
25     while(t--) {
26         scanf("%d%d",&n,&m);
27         for (int i=1;i<=n;++i) pre[i]=i,r[i]=1;
28         while(m--) {
29             int a,b;
30             scanf("%d%d",&a,&b);
31             join(a,b);
32         }
33         int cnt=0;
34         for (int i=1;i<=n;++i) if(i==pre[i]) cnt++;
35         printf("%d\n",cnt);
36     }
37     return 0;
38 }