Easter Calculator

#python #programming #computerscience #functional

# easter_calculator.py
#   This program takes a year as an input, verifies that it is in the proper
#   range, and then prints out the date of Easter that year.
# by: Scott Gordon

from datetime import datetime, timedelta

def main():
    print("Welcome To the Easter Calculator\n")
    print("Choose a year that you want to find the date of easter from 1982-2048")
    year = int(input("Please enter the year (yyyy) here: "))

    def easter_calc(year):
        """Takes year as input and prints out when Easter was that year."""
        a = year % 19
        b = year % 4
        c = year % 7
        d = ((19*a) + 24) % 30
        e = (2*b + 4*c + 6*d + 5) % 7

        start_date = datetime(year, 3, 22)
        format = "%m/%d/%y"
        easter = start_date + timedelta(d+e)

        if (year >= 1982) and (year <= 2048):
            return f"\nThe date of Easter is {easter.strftime(format)}"
        else:
            return f"\nSorry you must choose a year from 1982 to 2048."

    print(easter_calc(year))


if __name__ == "__main__":
    main()