gistfile1.txt

#!/usr/bin/env python3

year = input("Please enter a 4 digit year: ")
cenFloats = [2, 0, 5, 3]
weekdays = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]


def getMinorFloat(x):
    return ((x+int(x/4))%7)


def getCenturyFloat(x):
   return x % len(cenFloats)


def getWeekday(year):
  century = year // 100
  decade = year % 100
  minorFloat = getMinorFloat(decade)
  centuryFloat = cenFloats[getCenturyFloat(century)]
  return weekdays[(centuryFloat + minorFloat) % 7]


try:
    year = int(year)
    if not 1582 <= int(year) <= 9999:
        print("The Gregorian calendar was instituted by Pope Gregory XIII in 1582.\nOnly 4 digit number years excepted starting from 1582 on.")
    else:
        print(f"10/31/{year} was a {getWeekday(year)}")
except:
   print("Only 4 digit number years excepted starting from 1582 on.")
   exit