output_description: Output what day of the week it is in a line. Use the following conventions in
  your output: "mon" for Monday, "tue" for Tuesday, "wed" for Wednesday, "thu"
  for Thursday, "fri" for Friday, "sat" for Saturday, and "sun" for Sunday.
input_description: The input is given in the following format.
  
      
      
      X
      
  
  The input line specifies a day X (1 ≤ X ≤ 30) in September 2017.
attempt: X = int(input())
  Day = ["mon", "tue", "wed", "thu", "fri", "sat", "sun"]
  a = X % 7
  if a == 2 or a == 3:
      print(Day[a + 3])
  elif a == 4 or a == 5 or a == 6:
      print(Day[a - 4])
  elif a == 0 or a == 1:
      print(Day[a + 3])
  
problem_description: Day of Week
  
  The 9th day of September 2017 is Saturday. Then, what day of the week is the
  X-th of September 2017?
  
  Given a day in September 2017, write a program to report what day of the week
  it is.
samples: [{"input": "1", "output": "fri"}, {"input": "9", "output": "sat"}, {"input": "30", "output": "sat"}]