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

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

const int N=100001;

vector<int> a[N];
bool viz[N];
int n,m;


void citire()
{
    int i,x,y;
    in>>n>>m;
    for(i=1; i<=m; i++)
    {
        in>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    in.close();
}
void dfs(int nod)
{
    viz[nod]=1;
    for(size_t i=0; i<a[nod].size(); i++)
        if(viz[a[nod][i]]==0)
                dfs(a[nod][i]);

    }

int main()
{
    int i,ncc=0;
    citire();
    for(i=1; i<=n; i++)
        if(viz[i]==0)
        {
            ncc++;
            dfs(i);
        }
    out<<ncc;
    return 0;
}