#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

int n;
bool viz[100001];
vector <int> graf[100001];


void citire(){
    int m,a,b;

    f>>n;
    f>>m;

    for(int i=1; i<=m; i++){

        f>>a>>b;
        graf[a].push_back(b);
        graf[b].push_back(a);

    }

}

void DFS(int nod){

    viz[nod] = 1;

    for(int i=0; i<graf[nod].size(); i++){

        int vecin  = graf[nod][i];
        if(viz[vecin]==0)
            DFS(vecin);

    }

}

int main(){

    citire();

    for(int i=1;i<=n;i++)
        viz[i] = 0;

    int comp = 0;

    for(int i=1; i<=n; i++){

        if(viz[i]==0){

            comp++;
            DFS(i);

        }

    }
    g<<comp;
    return 0;

}