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

ofstream fo("dfs.out");
ifstream fi("dfs.in");


int n,m,a,b;
vector <int> vecini[100004];
int viz[100005],s;
void DFS(int curent)
{
    viz[curent]=true;

    for(auto v:vecini[curent])
        if(viz[v]==false)
            DFS(v);
}
int main()
{
    fi>>n>>m;

    for(int i=1; i<=m; i++)
    {
        fi>>a>>b;
        vecini[a].push_back(b);
        vecini[b].push_back(a);
    }

    for(int i=1; i<=n; i++)
        if(viz[i]==false)
        {
            s++;
            DFS(i);
        }


    fo<<s;
    fi.close();
    fo.close();
    return 0;
}