#include <bits/stdc++.h>
using namespace std;
int main() {
  double a, b, c, d, e, f, g, h;
  while (scanf("%lf,%lf,%lf,%lf,%lf,%lf,%lf,%lf", &a, &b, &c, &d, &e, &f, &g,
               &h) != EOF) {
    if ((a == c && g == e && d == f && b == h) ||
        (a == g && c == e && b == d && h == f))
      cout << "YES" << endl;
    else
      cout << "NO" << endl;
  }
}
