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

using namespace std;

ifstream f("dfs.in");
ofstream g("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;
     f>>n>>m;
     adj.resize(n+5);
     viz.resize(n+5);
     for(int i = 1; i<=m ; i++)
     {
        int x,y;
        f>>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++;
     }
     g<<cnt;

     return 0;
}