#include <stdio.h>
#include <vector>
using namespace std;
vector <int> v[100001];
int viz[100001];
void dfs(int nod) {
    int i; viz[nod]=1;
    for(i=0;i<v[nod].size();i++) {
        if(!viz[v[nod][i]]) {
            dfs(v[nod][i]);
        }
    }
}
int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    int n, m, x, y, i, cc=0;
    scanf("%d%d",&n,&m);
    for(i=1;i<=m;i++) {
        scanf("%d%d",&x,&y);
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(i=1;i<=n;i++) {
        if(!viz[i]) {
            dfs(i);
            cc++;
        }
    }
    printf("%d",cc);
    return 0;
}