1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 const int MAX=1001;
 5 int fa[MAX];
 6 int n;
 7 int m;
 8 using namespace std;
 9 void init()
10 {
11     int i;
12     for(i=0;i<=n;++i)
13     fa[i]=i;
14 }
15 int find_father(int x)
16 {
17     while(x!=fa[x])
18     {
19         x=fa[x];
20     }
21     return x;
22 }
23 void join_tree(int x,int y)
24 {
25     int a,b;
26     a=find_father(x);
27     b=find_father(y);
28     if(a!=b)
29     fa[a]=b;
30 }
31 int main()
32 {
33     int t,m,a,b,i,sum;
34     cin>>t;
35     while(t--)
36     {
37         cin>>n>>m;
38         sum=0;
39         init();
40         while(m--)
41         {
42             cin>>a>>b;
43             join_tree(a,b);
44         }
45         for(i=1;i<=n;i++)
46         if(fa[i]==i)//如果他的父亲是自己则桌子加一
47         sum+=1;
48         cout<<sum<<endl;
49     }
50     return 0;
51 }