#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");
const int maxN = 100000;
vector<int> graf[maxN + 1];
bool viz[maxN + 1];
///DFS
void dfs(int nod)
{
    viz[nod] = true;
    for (int vecin : graf[nod])
        if (!viz[vecin])
            dfs(vecin);
}



int main()
{
    int N, M;
    f>> N >> M;

    for (int i = 0; i < M; i++)
    {
        int x, y;
        f>> x >> y;
        graf[x].push_back(y);
        graf[y].push_back(x);
    }

    int nrcomp = 0;
    for (int i = 1; i <= N; i++)
    {
        if (!viz[i])
        {
            dfs(i);
            nrcomp++;
        }
    }

    g<< nrcomp;

}