#include <fstream>
#include <vector>

using namespace std;

ifstream in ("dfs.in");
ofstream out ("dfs.out");
const int N = 100005;

vector <int> g[N];

int n, m, ncomp;
bool viz[N];

void dfs(int x)
{
    for(int i = 0; i < g[x].size(); i++)
    {
        if(viz[g[x][i]] == false)
            {
                viz[g[x][i]] = true;
                dfs(g[x][i]);
            }
    }

}

int main()
{
    in >> n >> m;
    int i, a, b;
    for(i = 1; i <= m; i++)
    {
        in >> a >> b;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    for(i = 1; i <= n; i++)
        if(viz[i] == false)
            {
                dfs(i);
                ncomp++;
            }
    out << ncomp;

    return 0;
}