#include <iostream>
#include <vector>
#include <fstream>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector<int>G[100];
int viz[100005], n, m, x, y;
void citire_graf(){
    fin>>n>>m;
    for(int i=1;i<=m;i++){
        fin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    fin.close();
}
void dfs(int nod){
    viz[nod]=1;
    for(int i=0; i<G[nod].size(); i++){
        if(!viz[G[nod][i]])
            dfs(G[nod][i]);
    }
}
int main()
{
    citire_graf();
    int conexe = 0, k=1;
    for(k=1; k<=n;k++){
        if(viz[k]==0){
            dfs(k);
        conexe++;
        }

    }
    fout<<conexe;
    return 0;
}