#include <fstream>
#include <vector>
#include <bitset>

using namespace std;

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

const int MAXN = 100005;

vector < int > v[MAXN];
bitset < MAXN > viz;

void dfs(int nod)
{
    viz[nod] = 1;
    for (auto &it : v[nod])
    {
        if (!viz[it])
        {
            dfs(it);
        }
    }
}

int main()
{
    int n, m, i, x, y, cnt = 0;
    fin >> n >> m;
    for (i = 1; i <= m; ++i)
    {
        fin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for (i = 1; i <= n; ++i)
    {
        if (!viz[i])
        {
            ++cnt;
            dfs(i);
        }
    }
    fout << cnt << '\n';
    return 0;
}