#include <iostream>
#include <vector>
#include <cstdio>
#define MAXN 100005
using namespace std;

int n, m;
vector< vector<int> > a(MAXN);
int viz[MAXN];

void citire() {
    int x, y;
    scanf("%d %d", &n, &m);
    for(int i = 0; i < m; i++) { // citeste muchii
        scanf("%d %d", &x, &y);
        a[x].push_back(y);
        a[y].push_back(x);
    }
}

void dfs(int i) {
    viz[i] = 1;
    for(int j = 0; j < a[i].size(); j++)
        if(viz[a[i][j]] == 0)
            dfs(a[i][j]);
}

int componente_conexe() {
    int nr = 0;
    for(int i = 1; i <= n; i++) {
        if(viz[i] == 0) {
            dfs(i);
            nr++;
        }
    }
    return nr;
}
int main()
{
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);

    citire();
    printf("%d\n", componente_conexe());
    return 0;
}