#include <fstream>
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <vector>
using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

int visited[100001];

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

    for (auto neigh : adj[node])
        if (visited[neigh] == 0)
            dfs(neigh, adj);
}

int main() {
    int n, m;
    fin >> n >> m;

    vector<int> adj[1000001];
    for (int i = 1; i <= m; i++) {
        int x, y;
        fin >> x >> y;

        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    int solution = 0;
    for (int i = 1; i <= n; i++)
        if (visited[i] == 0) {
            solution++;
            dfs(i, adj);
        }

    fout << solution;
}