#include <bits/stdc++.h>

using namespace std;

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

vector <int> V[100005];

int n,m,nrc;

bool seen[100005];

int dfs(int nod)
{
    seen[nod] = 1;

    for(auto vecin:V[nod])
    {
        if(seen[vecin] == 0)
        dfs(vecin);
    }
}

int main()
{
    fin>>n>>m;

    for(int i = 1;i<=m;i++)
    {
        int a,b;

        fin>>a>>b;

        V[a].push_back(b);
        V[b].push_back(a);
    }
    for(int i = 1;i<=n;i++)
    {
        if(seen[i] == 0)
            {
                nrc++;
                dfs(i);
            }
    }
    fout<<nrc;
}