#include <fstream>
#include <vector>

using namespace std;

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

int n,m,viz[100002],conComp,a,b;

vector <int> graph[100005];

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

int main () {

    fin>>n>>m;
    for (int i=1; i<=m; i++){
        fin>>a>>b;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }

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

    fout<<conComp;

    return 0;
}