#include <fstream>

using namespace std;

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

int n, m, x, a[101][101], viz[101], mx = 1;

void citire() {
    f >> n >> m;
    int i, j;
    while(f >> i >> j) {
        a[i][j] = a[j][i] = 1;
    }
}

void DFS(int nod) {
    viz[nod] = 1;
    for(int i = 1; i <= n; ++i)
        if(!viz[i] && a[nod][i] == 1) {
            mx++;
            DFS(i);
        }
}

int main()
{
    citire();
    DFS(1);
    g << mx;
    g.close();
    f.close();
    return 0;
}