#include <iostream>
#include <fstream>
#include <vector>
#include <bitset>
using namespace std;
ifstream fin ("dfs.in");
ofstream fout ("dfs.out");
vector <int> G[100001];
bitset <100001> viz;
int n, m, nr;
void dfs(int nod)
{
    viz[nod]=1;
    for(unsigned i=0; i<G[nod].size(); ++i)
        if(viz[G[nod][i]]==0)
            dfs(G[nod][i]);
    ///punctul in care toti fii sunt vizitati
}
int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; ++i)
    {
        int x, y;
        fin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for(int i=1; i<=n; ++i)
        if(viz[i]==0)
        {
            nr++;
            dfs(i);
        }
    fout<<nr;
}