text: # 없는 숫자 찾기
  
  
  def solution(numbers):
      ret = 0
      s = set(numbers)
      for i in range(10):
          if i not in s:
              ret += i
      return ret
  
  
  if __name__ == "__main__":
      numbers = [1, 2, 3, 4, 6, 7, 8, 0]
      print(solution(numbers=numbers))