#include <bits/stdc++.h>

using namespace std;

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

const int NMAX = 1e5;
const int INF = 1e9;
vector<int> G[NMAX + 1];
queue<int> q;
int vis[NMAX + 1];
int n, m;

void dfs(int node) {
    //cout << node << ' ';
    vis[node] = 1;
    for(int i = 0; i < G[node].size(); i++) {
        int vecin = G[node][i];
        if(!vis[vecin]) {
            dfs(vecin);
        }
    }
}

int main() {
    f >> n >> m;
    for(int i = 1; i <= m; i++) {
        int x, y;
        f >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x); //daca avem un graf orientat linia asta dispare
    }
    int nrcc = 0;
    for(int i = 1; i <= n; i++) {
        if(!vis[i]) {
            nrcc++;
            dfs(i);
            //cout << '\n';
        }
    }
    g << nrcc;
    return 0;
}