Problem F
Thank God it’s Friday

A wall calendar displaying the date 10 OCT. From the remains of the newspaper we can infer that January 1 was a Monday.

Friday is the highlight of Børge and Åse’s life. They can meet up with their buddies in the ITU Friday bar and discuss anything they want: the weather, sports, favourite editors, politics, religion, and gossip about celebrities. Life can be good.

Unfortunately, they don’t know which day of the week it is! They’ve woken up in a strange apartment, phones missing, and with little memory of the recent past. Which day is it? Which year is it even?

After some searching, they establish today’s date, because the calendar on the wall displays it. Also, Åse has found the remains of an old newspaper from 1 January in her handbag, which has that weekday printed on the front page.

Help Børge and Åse figure out if today is Friday.


On the first line, today’s date. The date consists of two parts, separated by space. The first part is in an integer (the day of the month) $d$, with $1\leq d\leq 31$. The second part is the name of the month, abbreviated as JAN, FEB, MAR, APR, MAY, JUN, JUL, AUG, SEP, OCT, NOV, or DEC.

On the second line, the name of the day on 1 January of the current year, abbreviated as MON, TUE, WED, THU, FRI, SAT, SUN.


Output a single line: The four letters TGIF, abbreviating “Thank God it’s Friday” if today is certainly Friday. The two words not sure if today might be Friday, depending on if this year has a 29th of February. The emoticon :( if today is certainly not Friday.

Sample Input 1 Sample Output 1
10 OCT
Sample Input 2 Sample Output 2
Sample Input 3 Sample Output 3
29 NOV
not sure

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