#include <bits/stdc++.h>

using namespace std;

void dfs(int node, vector<vector<int>> &g, vector<bool> &viz)
{
    viz[node] = true;
    for (auto &x : g[node])
        if (!viz[x])
            dfs(x, g, viz);
}

int main()
{
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);

    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    int n, m;
    cin >> n >> m;

    vector<vector<int>> g(n + 2);

    for (int i = 1; i <= m; ++i)
    {
        int a, b;
        cin >> a >> b;

        g[a].push_back(b);
        g[b].push_back(a);
    }

    vector<bool> viz(n + 2, false);

    int cnt = 0;
    for (int i = 1; i <= n; ++i)
        if (!viz[i])
        {
            dfs(i, g, viz);
            ++cnt;
        }

    cout << cnt << '\n';

    return 0;
}