#include <cstdio>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;

int n, m;
vector<int> e[100100];
bool viz[100100];

void dfs(int x) {
    viz[x] = true;
    for (auto y : e[x]) {
        if (!viz[y]) {
            dfs(y);
        }
    }
}

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

    int x, y;

    scanf("%d %d", &n, &m);
    for (int i = 0; i < m; ++i) {
        scanf("%d %d", &x, &y);
        e[x].push_back(y);
        e[y].push_back(x);
    }
    int sol = 0;
    for (int i = 1; i <= n; ++i) {
        if (!viz[i]) {
            dfs(i);
            sol++;
        }
    }
    printf("%d\n", sol);

    return 0;
}