#include <fstream>
#include <vector>
using namespace std;

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

#define vecSize 100001

vector<int> L[vecSize]; // Lista de adiacenta
vector<int> viz(vecSize, 0);

void dfs(int node)
{
    viz[node] = 1;
    for (auto vec : L[node])
    {
        if (!viz[vec])
            dfs(vec);
    }
}

int main()
{
    int n, m;
    fin >> n >> m;

    for (int i = 1; i <= m; i++)
    {
        int x, y;
        fin >> x >> y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    int nr = 0;
    for (int i = 1; i <= n; i++)
    {
        if (viz[i] == 0)
        {
            nr++;
            dfs(i);
        }
    }

    fout << nr;

    return 0;
}