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

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

const int NMAX = 1e5+5;
vector<int> graf[NMAX];
bool vis[NMAX];

void dfs(int nod) {
    vis[nod] = 1;
    for(int i = 0; i < (int)graf[nod].size(); i++) {
        int next = graf[nod][i];
        if(!vis[next]) {
            dfs(next);
        }
    }
}
int main()
{
    int n, m;
    f >> n >> m;
    while(m--) {
        int x, y;
        f >> x >> y;
        graf[x].push_back(y);
        graf[y].push_back(x);
    }
    int sol = 0;
    for(int i = 1; i <= n; i++) {
        if(!vis[i]) {
            sol++;
            dfs(i);
        }
    }
    g << sol;
    return 0;
}