output_description: If c is a vowel, print `vowel`. Otherwise, print `consonant`.
  
  * * *
input_description: The input is given from Standard Input in the following format:
  
      
      
      c
attempt: S = input()
  n = 0
  # print(S)
  while S[:] != S[:n]:
      if S[n : n + 7] == "dreamer" and S[n : n + 8] != "dreamera":
          n += 7  # dreamer
      elif S[n : n + 5] == "dream":
          n += 5  # dream
      elif S[n : n + 5] == "erase" and S[n + 6] != "eraser":
          n += 5  # erase
      elif S[n : n + 6] == "eraser":
          n += 6  # eraser
      # elif S[:]==S[:n-1]:
      # print("YES")
      # exit()
      else:
          print("NO")
          exit()
  else:
      print("YES")
  
problem_description: Statement
  
  Given a lowercase English letter c, determine whether it is a vowel. Here,
  there are five vowels in the English alphabet: `a`, `e`, `i`, `o` and `u`.
samples: [{"input": "a", "output": "vowel\n    \n\nSince `a` is a vowel, print `vowel`.\n\n* * *"}, {"input": "z", "output": "consonant\n    \n\n* * *"}, {"input": "s", "output": "consonant"}]