#include <bits/stdc++.h>

using namespace std;

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

int n,m,x,y,nrcomp,viz[100005];
vector < int > v[100005];

void citire()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
}

void dfs(int nod)
{
    viz[nod]=1;
    for(auto k:v[nod])
    {
        if(!viz[k])
        {
            dfs(k);
        }
    }
}

int main()
{
    citire();
    for(int i=1; i<=n; i++)
    {
        if(!viz[i])
        {
            nrcomp++;
            dfs(i);
        }
    }
    fout<<nrcomp;
    return 0;
}