#include <bits/stdc++.h>
using namespace std;
const int MOD = 1000000007;
const int INF = 1000000001;
const long long LINF = 1000000000000000001LL;
int len[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
string days[] = {"monday", "tuesday",  "wednesday", "thursday",
                 "friday", "saturday", "sunday"};
int dayId(string s) { return find(days, days + 7, s) - days; }
int main() {
  ios_base::sync_with_stdio(0);
  string a, b;
  cin >> a >> b;
  int aid = dayId(a), bid = dayId(b);
  for (int i = (0); i <= (10); ++i) {
    if ((aid + len[i]) % 7 == bid) {
      cout << "YES";
      return 0;
    }
  }
  cout << "NO";
  return 0;
}
