output_description: Print `Yes` if S is easily playable, and `No` otherwise.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      S
attempt: odd = ["R", "U", "D"]
  even = ["L", "U", "D"]
  s_list = list(input())
  
  ans = "Yes"
  for i in range(s_list):
    if i % 2 == 0:
  	  if not s_list[i] in odd:
      	ans = "No"
    
    if i % 2 == 1:
  	  if not s_list[i] in even:
      	ans = "No"
  
  print(ans)
problem_description: Statement
  
  Takahashi will do a tap dance. The dance is described by a string S where each
  character is `L`, `R`, `U`, or `D`. These characters indicate the positions on
  which Takahashi should step. He will follow these instructions one by one in
  order, starting with the first character.
  
  S is said to be _easily playable_ if and only if it satisfies both of the
  following conditions:
  
    * Every character in an odd position (1-st, 3-rd, 5-th, \ldots) is `R`, `U`, or `D`.
    * Every character in an even position (2-nd, 4-th, 6-th, \ldots) is `L`, `U`, or `D`.
  
  Your task is to print `Yes` if S is easily playable, and `No` otherwise.
samples: [{"input": "RUDLUDR", "output": "Yes\n    \n\nEvery character in an odd position (1-st, 3-rd, 5-th, 7-th) is `R`, `U`, or\n`D`.\n\nEvery character in an even position (2-nd, 4-th, 6-th) is `L`, `U`, or `D`.\n\nThus, S is easily playable.\n\n* * *"}, {"input": "DULL", "output": "No\n    \n\nThe 3-rd character is not `R`, `U`, nor `D`, so S is not easily playable.\n\n* * *"}, {"input": "UUUUUUUUUUUUUUU", "output": "Yes\n    \n\n* * *"}, {"input": "ULURU", "output": "No\n    \n\n* * *"}, {"input": "RDULULDURURLRDULRLR", "output": "Yes"}]