output_description: If N contains the digit 7, print `Yes`; otherwise, print `No`.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
attempt: # coding: utf-8
  # Your code here!
  
  N = int(input())
  RGB = list(input())
  
  count = 0
  sub = 0
  
  
  def index_Multi(List):
      r_list = []
      g_list = []
      b_list = []
      for val in range(0, len(List)):
          if "R" == List[val]:
              r_list.append(val)
          elif "G" == List[val]:
              g_list.append(val)
          elif "B" == List[val]:
              b_list.append(val)
      return r_list, g_list, b_list
  
  
  r_list, g_list, b_list = index_Multi(RGB)
  
  for index, a in enumerate(RGB):
      if a == "R":
          del g_list[0 : len([i for i in g_list if i < index])]
          del b_list[0 : len([i for i in b_list if i < index])]
          for g in g_list:
              for b in b_list:
                  if g - index == b - g or b - index == g - b:
                      sub += 1
          count = count + len(g_list) * len(b_list)
  
      elif a == "G":
          del b_list[0 : len([i for i in b_list if i < index])]
          del r_list[0 : len([i for i in r_list if i < index])]
          for b in b_list:
              for r in r_list:
                  if b - index == r - b or r - index == b - r:
                      sub += 1
          count = count + len(b_list) * len(r_list)
  
      elif a == "B":
          del r_list[0 : len([i for i in r_list if i < index])]
          del g_list[0 : len([i for i in g_list if i < index])]
          for r in r_list:
              for g in g_list:
                  if r - index == g - r or g - index == r - g:
                      sub += 1
          count = count + len(g_list) * len(r_list)
  
  print(count - sub)
  
problem_description: Statement
  
  Given is a three-digit integer N. Does N contain the digit 7?
  
  If so, print `Yes`; otherwise, print `No`.
samples: [{"input": "117", "output": "Yes\n    \n\n117 contains 7 as its last digit.\n\n* * *"}, {"input": "123", "output": "No\n    \n\n123 does not contain the digit 7.\n\n* * *"}, {"input": "777", "output": "Yes"}]