#include <fstream>
#include <queue>
#define NMAX 100005

using namespace std;
ifstream in("dfs.in");
ofstream out("dfs.out");

int n, m, x, y;
vector <int> vecini[NMAX];
bool viz[NMAX];

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

int main()
{
    int i, j, cnt = 0;
    in >> n >> m;
    for (i = 1; i <= m; ++i)
    {
        in >> x >> y;
        vecini[x].push_back(y);
        vecini[y].push_back(x);
    }

    for (i = 1; i <= n; ++i)
    {
        if (viz[i] == 0)
        {
            dfs(i);
            ++cnt;
        }
    }

    out << cnt;
    return 0;
}