#include <iostream>
#include <cstdio>
#include <vector>
#define MAXN 100005

using namespace std;

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

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

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

    int t1, t2;
    scanf("%d %d", &n, &m);
    for (int i = 0; i < m; i++)
    {
        scanf("%d %d", &t1, &t2);
        a[t1].push_back(t2);
        a[t2].push_back(t1);
    }
    for (int i = 1; i <= n; i++)
        if (!viz[i])
        {
            nrcomp++;
            dfs(i);
        }
    printf("%d", nrcomp);

    return 0;
}