output_description: Print the answer.
  
  * * *
input_description: The input is given from Standard Input in the following format:
  
      
      
      N
attempt: N = int(input())
  s = str(input())
  ss = s
  
  if N % 2 == 1:
      s += s[0]
  if s[: len(s) / 2] * 2 != s:
      print(-1)
  else:
      ans = ""
      Flag = 0
      for c in ss:
          if Flag == 0:
              ans += "S"
              if c == "x":
                  Flag = 1
          else:
              if c == "x":
                  ans += "S"
                  Flag = 0
              else:
                  ans += "W"
      print(ans)
  
problem_description: Statement
  
  Snuke has a favorite restaurant.
  
  The price of any meal served at the restaurant is 800 yen (the currency of
  Japan), and each time a customer orders 15 meals, the restaurant pays 200 yen
  back to the customer.
  
  So far, Snuke has ordered N meals at the restaurant. Let the amount of money
  Snuke has paid to the restaurant be x yen, and let the amount of money the
  restaurant has paid back to Snuke be y yen. Find x-y.
samples: [{"input": "20", "output": "15800\n    \n\nSo far, Snuke has paid 16000 yen, and the restaurant has paid back 200 yen.\nThus, the answer is 15800.\n\n* * *"}, {"input": "60", "output": "47200\n    \n\nSnuke has paid 48000 yen for 60 meals, and the restaurant has paid back 800\nyen."}]