#include <bits/stdc++.h>

using namespace std;

ifstream f("dfs.in");
ofstream g("dfs.out");

vector<int> v[100001];
bool viz[100001];
int comp;

void dfs(int nod){
    int q;
    viz[nod]=1;
    for(int i=0; i< v[nod].size();i++){
        if(viz[v[nod][i]]==0){
        dfs(v[nod][i]);
        }
    }
}

int main()
{

    int n, m,i;
    int x,y;
    f>>n>>m;
    for(i=1; i<=m; i++){

        f>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);

    }

    for(i=1; i<=n; i++){
        if(viz[i]==0){
            dfs(i);
            comp++;
        }
    }

    g<<comp;

    return 0;
}