You are given a string S consisting of lowercase English letters. Another string T is initially empty. Determine whether it is possible to obtain S = T by performing the following operation an arbitrary number of times:    * Append one of the following at the end of T: `dream`, `dreamer`, `erase` and `eraser`.
s = input()

candi = ['dreamer', 'dream', 'eraser', 'erase']

for tmp in candi:
  s.replace(tmp,'')
if len(s) == 0:
  print('YES')
else:
  print('NO')
s = input().replace("eraser","").replace("erase","").replace("dreamer","").replace("dream","")
 
if s:
  print("NO")
else:
  print("YES")