#include <fstream>
#include <queue>
#include <algorithm>
#include <vector>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int n,m,x,y;
bool viz[100001];
vector<int>a[100001];
void dfs(int x){
    viz[x]=1;
    for(auto urm:a[x])
        if(viz[urm]==0)
            dfs(urm);

}
int main()
{
    fin>>n>>m;
    for(int i=1;i<=m;i++){
        fin>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
   int comp=0;
    for(int i=1;i<=n;i++)
        if(viz[i]==0){
            comp++;
            dfs(i);
        }
    fout<<comp;
    return 0;
}