#include <fstream>
#include <vector>


using namespace std;

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

int parc[100001];
vector<int> v[100001];

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


int main()
{
    int n,m,x,y,componente_conexe,i;
    cin>>n>>m;
    for(i=1;i<=m;i++){
        cin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    componente_conexe=0;
    for(i=1;i<=n;i++){
        if(!parc[i]){
            componente_conexe++;
            dfs(i);
        }
    }
    cout<<componente_conexe;
    return 0;
}