#include <fstream>
#include <vector>

using namespace std;

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

const int N = 10005;

vector < int > muchii[N];

bool vizitat[N];
unsigned int comp_conexe = 0;

void DFS (int nod)
{
    vizitat[nod] = true; ///l-am vizitat

    unsigned int lung = muchii[nod].size();
    for(unsigned int i = 0; i < lung; i++)
    {
        int vecin = muchii[nod][i];
        if(!vizitat[vecin]) ///daca nu a fost vizitat
        {
            DFS(vecin);
        }
    }
}

int main()
{
    int n, m, x, y;
    in >> n >> m;

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

    for(int i = 1; i <= n; i++)
    {
        if(!vizitat[i]) ///daca nu am vizitat nodul i
        {
            comp_conexe += 1;
            DFS(i);
        }
    }

    out << comp_conexe;

    in.close();
    out.close();
    return 0;
}