#include <iostream>
#include <fstream>
#include <vector>
#define Nmax 100005
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

vector <int> L[Nmax];
int m,n;
int v[Nmax];


void DFS(int x)
{

    int i;
    if(v[x]==0)
    {
    v[x]=1;
    for(int unsigned i=0;i<L[x].size();i++)
      DFS(L[x][i]);

    }
}

void Citire()
{
    int i,x,y;
    fin>>n>>m;
    for(i=1;i<=m;i++)
    {
        fin>>x>>y;
        L[x].push_back(y);
        L[y].push_back(x);

    }
}


int main()
{
    Citire();
    int cnt=0;
    for(int i=1;i<=n;i++)

        if(v[i]==0){
            cnt++;
            DFS(i);

        }

    cout<<cnt;
    return 0;
}