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

static constexpr int NMAX = 100005;
int n, m;
vector<int> adj[NMAX];
int comp;

void dfs_rec(int node, vector<int>& visited) {
    visited[node] = 1;

    for (auto neigh : adj[node]) {
        if (!visited[neigh]) {
            dfs_rec(neigh, visited);
        }
    }
}
int main() {
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");

    fin >> n >> m;
    for (int i = 1, x, y; i <= m; i++) {
        fin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    fin.close();

    comp = 0;
    vector<int> visited(n + 1);
    for (int i = 1; i <= n; i++) {
        if (!visited[i]) {
            dfs_rec(i, visited);
            comp++;
        }
    }

    fout << comp << endl;
    fout.close();
    return 0;
}