#include <iostream>
#include <fstream>
#include <vector>

#define NMAX 100005
using namespace std;

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

int n, m, x, y, viz[NMAX], comp_conexe;
vector<int> ad[NMAX];

void dfs (int nod_crt)
{
    viz[nod_crt]=1;
    for(auto &vecin: ad[nod_crt])
        if(!viz[vecin])
            dfs(vecin);
}

int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fin>>x>>y;
        ad[x].push_back(y);
        ad[y].push_back(x);
    }
    for(int i=1; i<=n; i++)
        if(!viz[i])
        {
            dfs(i);
            comp_conexe++;
        }
    fout<<comp_conexe;
    return 0;
}