#include <fstream>
#include <vector>
#define nmax (int)(1e5+1)
using namespace std;
ifstream cin("dfs.in");
ofstream cout("dfs.out");
int n,m,x,y,c;
bool viz[nmax];
vector<int>v[nmax];
void dfs(int nod){
    viz[nod]=1;
    for(auto i:v[nod])
        if(!viz[i])
            dfs(i);
}
int main()
{
    cin>>n>>m;
    for(int i=1;i<=m;i++){
        cin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i=1;i<=n;i++)
        if(!viz[i]){
            c++;
            dfs(i);
        }
    cout<<c;
    return 0;
}