#include <fstream>
#include <vector>
using namespace std;

ifstream cin("dfs.in");
ofstream cout("dfs.out");

vector<vector<int>> v;
vector<int> viz;

void dfs(int nod){
    int i;
    viz[nod]=1;
    for(i=0;i<v[nod].size();i++){
        if(!viz[v[nod][i]]) dfs(v[nod][i]);
    }
}

int main()
{
    int n,m,cnt=0,i,a,b;
    cin>>n>>m;
    v.resize(n+1);viz.resize(n+1);
    for(i=0;i<m;i++){
        cin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    for(i=1;i<=n;i++){
        if(!viz[i]){
            dfs(i);
            cnt++;
        }
    }
    cout<<cnt;
    return 0;
}