#include<bits/stdc++.h>

using namespace std;

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

int n, m;

vector<vector<int > > adj;
vector <int > viz;


void DFS (int nod)
{
    viz[nod] = 1;
    for(int i: adj[nod])
        if (viz[i]==0)
        DFS(i);
}
int main()
{
    int cnt=0; ///numara comp conexe
    fin>>n>>m;
    adj.resize(n+5);
    viz.resize(n+5);
    for(int i=1; i<=m; i++){
        int x, y;
        fin>>x>>y;
        adj[x].push_back(y);
        adj[y].push_back(x);

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

     if(viz[i]==0)
        {
    DFS(i);
    cnt++;}
    }
    fout<<cnt;
    return 0;
}