#include <stdio.h>
#include <vector>
using namespace std;

const int MAXN = 100001;

bool viz[MAXN];

int n,m;

vector <int> v[MAXN];
void dfs(int nod){

    viz[nod] = true;
    for(int i = 0; i < v[nod].size(); i++)
    {
        if(viz[v[nod][i]] == false)
        {
            dfs(v[nod][i]);
        }
    }

}

int main(){

    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    scanf("%d%d",&n,&m);

    for(int i=1;i<=m;i++)
    {
        int a,b;
        scanf("%d%d",&a,&b);
        v[a].push_back(b);
        v[b].push_back(a);
    }


    int nrc = 0;
    for(int i = 1; i <= n; i++)
    {
        if(viz[i]== false){
            dfs(i);
            nrc++;
        }
    }
    printf("%d",nrc);
    return 0;
}