# Arup Guha
# 1/25/2012
# Leap Year

def main():

    # Get the year from the user.
    year = int(input("Please enter a year."))

    # All leap years are divisible by 4.
    if year%4 == 0:

        # Screen out the ones divisible by 100 and not 400.
        if year%100 == 0 and year%400 != 0:
            print(year,"is not a leap year.")

        else:
            print(year,"is a leap year.")

    else:
        print(year,"is not a leap year.")

main()