#include <iostream>
#include <vector>
#include <fstream>
using namespace std;

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

vector<vector<int>> ma;
vector<bool> v;

vector<int>::iterator k;

void dfs(int nod)
{
    v[nod]=1;
    vector<int>::iterator k;
    for(k=ma[nod].begin();k!=ma[nod].end();k++)
    {
        if(v[*k]==0)
        {
            dfs(*k);
        }

    }
}

int main()
{
    int n,m;
    fin>>n>>m;
    for(int c=0;c<=n;c++)
    {
        ma.push_back(vector<int> ());
        v.push_back(0);
    }

    int n1,n2;
    for(int c=1;c<=m;c++)
    {
        fin>>n1>>n2;
        ma[n1].push_back(n2);
        ma[n2].push_back(n1);
    }
    int cont=0;
    for(int c=1;c<=n;c++)
    {
        if(v[c]==0)
        {
            ++cont;
            dfs(c);
        }

    }
    fout<<cont;
    return 0;
}