#include <bits/stdc++.h>
int t1, t2;
inline int get() {
  char c[10];
  scanf("%s", &c);
  if (!strcmp(c, "monday")) return 1;
  if (!strcmp(c, "tuesday")) return 2;
  if (!strcmp(c, "wednesday")) return 3;
  if (!strcmp(c, "thursday")) return 4;
  if (!strcmp(c, "friday")) return 5;
  if (!strcmp(c, "saturday")) return 6;
  if (!strcmp(c, "sunday")) return 0;
}
int main() {
  t1 = get(), t2 = get();
  if ((t1 == t2) || ((t1 + 2) % 7 == t2) || ((t1 + 3) % 7 == t2))
    puts("YES");
  else
    puts("NO");
  return 0;
}
