#include <bits/stdc++.h>

using namespace std;

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

int n, m, x, y, viz[100005], nrComponente;
vector <int> v[100005];

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


int main()
{
    f >> n >> m;
    for(int i = 1; i <= m; i++){
        f >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }

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

    g << nrComponente;

    return 0;
}