#import string module 
import string

#This function takes as input the string representatio of a day
#and returns the int representation of the day
def weekday(day):
    if day == "monday":
        return 1
    elif day == "tuesday":
        return 2
    elif day == "wednesday":
        return 3
    elif day == "thursday":
        return 4
    elif day == "friday":
        return 5
    elif day == "saturday":
        return 6
    elif day == "sunday":
        return 7
    else:
        return 0

#ask the user for a day
current_day = raw_input("Enter the day: ")
#convert string entered by user to all lower case
current_day_lower = string.lower(current_day)

#call function to convert string representation of day to int representation
#store result in weekdaynum
weekdaynum = weekday(current_day_lower)

#if user entered friday, print TGIF
if weekdaynum == 5:
    print "TGIF!"
#if user entered sat or sun, print weekend message
elif 6 <= weekdaynum <= 7:
    print "It's the weekend!"
#if user entered mon - thurs, print work message
elif 1 <= weekdaynum <= 4:
    print "Back to work"
#otherwise, print invalid input message
else:
    print "Invalid day"