#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

int mt[100][100], x, y, n, m, nrcomp, v[100000], nr, p;
void citire()
{
    fin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        fin >> x >> y;
        mt[x][y] = 1;
        mt[y][x] = 1;
    }
}

void DFS(int nr)
{
    v[nr] = nrcomp;
    for (int i = 1; i <= n; i++)
        if (mt[nr][i] == 1 && v[i] == 0)
            DFS(i);
}

void comp()
{
    for (int i = 1; i <= n; i++)
        if (v[i] == 0)
        {
            nrcomp++;
            DFS(i);
        }
}

int main()
{
    citire();
    comp();
    fout << nrcomp;
}