#include <fstream>
#include <vector>
#define DIM 100002
using namespace std;

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

int n,m,x,y, comp;
bool viz[DIM];
vector<int> graf[DIM];

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


int main()
{
    in>>n>>m;
    for(int i=1; i<=m;i++){
        in>>x>>y;
        graf[y].push_back(x);
        graf[x].push_back(y);

    }
    for(int i=1;i<=n;i++){
        if(viz[i]==0){
            dfs(i);
            comp++;
        }
    }
    out<<comp;

    return 0;
}