#include<cstdio>
#include<vector> 
using namespace std; 
int n,m,nr;
vector<int> a[100010], b [100010];
bool aux[100010];
void citire();
void dfs(int); 
int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    citire();
    for(int i=1;i<=n;++i)
        if(aux[i]==0)
        {
            ++nr;
            dfs(i);
        }
    printf("%d ", nr);     
    return 0;
}
void citire()
{
    int x,y;
    scanf("%d%d ", &n,&m);
	while(m--)
    {
        scanf("%d%d ", &x,&y);
        a[x].push_back(y);
		a[y].push_back(x);    
	}
} 
void dfs(int nod)
{
    aux[nod]=1;
    b[nr].push_back(nod);
    for(size_t i=0; i<a[nod].size();++i)
    {
		if(!aux[a[nod][i]])
        {
           dfs(a[nod][i]);
        }
	}
}