#include <bits/stdc++.h>
#define NMAX 100010
using namespace std;

int n, m;
int viz[NMAX];
vector <int> adj[NMAX];

void dfs(int node) {
    viz[node] = 1;

    for (int neigh : adj[node]) {
        if (!viz[neigh]) {
            dfs(neigh);
        }
    }
}

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

    for (int node = 1; node <= n; node++) {
        viz[node] = 0; 
    }

    int count = 0;
    for (int node = 1; node <= n; node++) {
        if (!viz[node]) {
            dfs(node);
            count++;
        }
    }

    cout << count << "\n";
}