#include <bits/stdc++.h>

using namespace std;

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

vector<int> adj[100005];
int n, m, x, y, viz[100005];

void dfs(int start) {

    for (auto it : adj[start]) {
        if (!viz[it]) {
            viz[it] = 1;
            dfs(it);
        }
    }
}

int main() {
    in >> n >> m;
    for (int i = 1; i <= m; i++) {
        cin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    int comp = 0;
    for (int i = 1; i <= n; i++) {
        if (!viz[i]) {
            dfs(i);
            comp++;
        }
    }
    out << comp;
    return 0;
}