#include <fstream>
#include <vector>

using namespace std;

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

int nrcomp, n, m, x1, x2;
bool viz[100005];
vector<int> v[100005];

void DFS(int x)
{int y;
    viz[x] = 1;
    for(unsigned int i=0; i<v[x].size(); i++){
         y=v[x][i];
        if(!viz[y]) DFS(y);
    }
}

int main()
{
    f >> n >> m;
    for(int i=1; i<=m; i++)
    {
        f >> x1 >> x2;
        v[x1].push_back(x2);
        v[x2].push_back(x1);
    }
    for(int i=1; i<=n; i++){
        if(!viz[i]){
          nrcomp++;
          DFS(i);
        }
    }
    g << nrcomp ;
    return 0;
}