#include <fstream>
#include <vector>

using namespace std;

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

const int Nmax = 100005;

int n,m;
bool viz[Nmax];
vector<int> L[Nmax];

void dfs(int nod){
    viz[nod] = 1;
    for(int vec : L[nod]){
        if(!viz[vec])
            dfs(vec);
    }
}

int main()
{
    int i,x,y,nr;
    fin >> n >> m;
    for(i=1;i<=m;i++){
        fin >> x >> y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    nr = 0;
    for(i=1;i<=n;i++){
        if(!viz[i]){
            nr++;
            dfs(i);
        }
    }
    fout << nr;
    return 0;
}