#include <bits/stdc++.h>
#define N 100001

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int noduri,muchii,nrComponente;
vector<int> ListaMuchii[N];
int viz[N];

void DFS(int nod)
{
    viz[nod]=1;
    for(auto x:ListaMuchii[nod])
        if(!viz[x])
            DFS(x);
}


int main()
{
    fin>>noduri>>muchii;
    for(int i=1;i<=muchii;++i)
    {
        int x1,y1;
        fin>>x1>>y1;
        ListaMuchii[x1].push_back(y1);
        ListaMuchii[y1].push_back(x1);
    }
    for(int i=1; i<=noduri; ++i)
        if(!viz[i])
        {
            nrComponente++;
            DFS(i);
        }
    fout<<nrComponente<<'\n';
    return 0;
}