#include <iostream>
#include <vector>
#include <queue>

using namespace std;

int N;
vector< vector<int> > G;
vector<int> visited;

int dfs(int s) {
    for (int i = 0; i < G[s].size(); i++) {
        if (!visited[G[s][i]]) {
            visited[G[s][i]] = 1;
            dfs(G[s][i]);
        }
    }
}

main() {
    int n, m;
    int x, y;

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

    scanf("%d%d", &n, &m);

    N = n + 1;
    G = vector< vector<int> >(N, vector<int>());

    for (int i = 0; i < m; i++) {
        scanf("%d%d", &x, &y);
        G[x].push_back(y);
        G[y].push_back(x);
    }

    int count = 0;
    visited = vector<int>(N, false);

    for (int i = 1; i <= n; i++) {
        if (!visited[i]) {
            dfs(i);
            count++;
        }
    }

    printf("%d\n", count);
}