#include <fstream>
#include <vector>
using namespace std;
ifstream cin("dfs.in");
ofstream cout("dfs.out");
const int N = 100005;
vector <int>v[N];
bool viz[N];
int n,m;
void dfs(int nod){
    viz[nod] = 1;
    int i;
    for(i = 0;i < v[nod].size();i++){
        if(!viz[v[nod][i]])
            dfs(v[nod][i]);
    }
}
int main()
{
    int x,y,cnt = 0,i;
    cin >> n >> m;
    for(i = 1;i <= m;i++){
        cin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(i = 1;i <= n;i++){
        if(!viz[i]){
            cnt++;
            dfs(i);
        }
    }
    cout << cnt;
    return 0;
}