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

int n, m;
vector<vector<int>> v(100001);
bool vis[100001];

void dfs(int node) {
    vis[node] = 1;
    for (int i = 0; i < v[node].size(); ++i) {
        if (!vis[v[node][i]]) {
            dfs(v[node][i]);
        }
    }
    return;
}

int main() {
    ifstream cin("dfs.in");
    ofstream cout("dfs.out");
    cin >> n >> m;
    for (int i = 1; i <= m; ++i) {
        int x, y;
        cin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    int ans = 0;
    for (int i = 1; i <= n; ++i) {
        if (!vis[i]) {
            ++ans;
            dfs(i);
        }
    }
    cout << ans;
}