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

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

vector<vector<int>> v(100001);
vector<bool> viz(100001, false); 

int sol;

void dfs(int s) {
    viz[s] = true;
    for(auto&& nod : v[s])
    {
        if (!viz[nod]) {
            dfs(nod);
        }
        
    }
    
}

int main() {
    int n, m;
    int x, y;
    in >> n >> m;
    for(int i = 0; i < m; i++)
    {
        in >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i = 1; i <= n; i++)
    {
        if (!viz[i]) {
            dfs(i);
            sol++;
        }
        
    }
    out << sol;
    return 0;
}