#include <iostream>
#include <vector>
using namespace std;
#include <fstream>
std::ifstream g("dfs.in");
std::ofstream f("dfs.out");
const int nlim = 10010;
vector<vector<int>> muchii;
vector<bool> verif;
void dfs(int p)
{
    verif[p] = 1;
    for (unsigned int i=0;i<muchii[p].size();i++)
       if(!verif[muchii[p][i]])
        dfs(muchii[p][i]);
}
int main()
{


    int n, m;
    
    g >> n >> m;
    muchii.resize(n+1);
    verif.resize(n+1,0);
    for (int i = 1; i <= m; i++)
    {
        int x, y;
        g >> x >> y; 
        muchii[x].push_back(y);
        muchii[y].push_back(x);
    }
    int nr = 0;
    for (int i = 1; i <=n; i++)
    {
        if (verif[i] == 0)
        {
            dfs(i);
            nr++;
        }
    }
   
    f << nr;

    return 0;
}