#include<fstream>
#include<vector>
using namespace std;

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



vector<int> nod[100010];
bool viz[100005];

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


int main(){
    int n, m;
    in>>n>>m;

    for(int i =0; i<m; ++i){
        int x, y;
        in>>x>>y;
        nod[x].push_back(y);
        nod[y].push_back(x);
    }
int k = 0;
    for(int i = 1 ; i<=n; ++i){

               if(viz[i]==0){ dfs(i);
                    ++k;
               }
    }

    out<<k;


    return 0;
}