#include <iostream>
#include <bits/stdc++.h>
using namespace std;

vector<int> L[100001];
int vis[100001];

void dfs(int node) {
    vis[node] = 1;
    for (auto vec : L[node]) {
        if (vis[vec] == 0) {
            dfs(vec);
        }
    }
}
int main() {
    int n, m;
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        int x, y;
        cin >> x >> y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    int nr = 0;
    for (int i = 1; i <= n; i++) {
        if (vis[i] == 0) {
            nr++;
            dfs(i);
        }
    }
    cout << nr; // nr componente conexe
    return 0;
}