#include <fstream>
#include <vector>
#include <bitset>
using namespace std;
ifstream cin("dfs.in");
ofstream cout("dfs.out");
const int Nmax = 100001;
int n, m, x, y, ncc;
vector<vector<int>> graf;
bitset<Nmax> viz;
void dfs(int nod)
{
    viz[nod] = 1;
    for(auto next:graf[nod])
        if(!viz[next])
            dfs(next);
}
int main()
{
    cin >> n >> m;
    graf.assign(n+1, vector<int>());
    for(int i=1; i<=m; i++)
    {
        cin >> x >> y;
        graf[x].push_back(y);
        graf[y].push_back(x);
    }
    for(int i=1; i<=n; i++)
        if(!viz[i])
        {
            ncc++;
            dfs(i);
        }
    cout << ncc;
    return 0;
}