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