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

ifstream f("dfs.in");
ofstream g("dfs.out");

vector<int>G[100002];


int viz[100002];
int i,n,pl,j,m,x,y;

void parc_adancime(int plecare) {
int i;
viz[plecare]=1;//marcam nodul de plecare ca fiind vizitat
for (i=0;i<G[plecare].size();i++)
    if (viz[G[plecare][i]] == 0)    {
        parc_adancime(G[plecare][i]);
    }

}

int main()
{
    f>>n>>m;
    for (i=1;i<=m;i++)  {
        f>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);

    }

    int nr=0;
    for (i=1;i<=n;i++)
        if (viz[i] == 0)    {
            nr++;
            parc_adancime(i);
        }
    g<<nr;
    return 0;
}