#include <fstream>
#include <bits/stdc++.h>

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
bool v[100003];
vector<int> yes[100003];
void dfs(int poz)
{
    v[poz]=1;
    for (auto y: yes[poz])
        {
            if(!v[y])
               dfs(y);
        }
}
int main()
{
    int n,m,a,b,rez=0;
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>a>>b;
        yes[a].push_back(b);
        yes[b].push_back(a);
    }
    for(int i=1;i<=n;i++)
        {
            if(!v[i])
            {
                rez++;
                dfs(i);
            }
        }
    fout<<rez;
    return 0;
}