Decrypt the following messages encrypted using the caesar cipher f(p)=(p+3) mode 26

Question

Decrypt the following messages encrypted using the Caesar cipher $f(p)=(p+3)\; mod\;$26

Alphabet: A,B,C,D,E,F,G,H,I,......,Z

Entered HDW GLP VXP

my answer is: KGZ JOS YAS

but my answer is wrong

Answer 1

Hint. I think you encrypted the already encrypted message. What function decrypts?

Answer 2

!!DECRYPT!! the following messages encrypted using the Caesar cipher f(p)=(p+3)mod

26

Alphabet: A,B,C,D,E,F,G,H,I,......,Z

Final message (AFTER it was encrypted) is: HDW GLP VXP

my answer is: KGZ JOS YAS

but my answer is wrong

====

The ORIGINAL message was ??????. It was !!EN!!crypted by adding 3 so to get HDW GLP VXP.

So we need ??? ??? ??? ---- +3 -----> HDW GLP VXP

What you did was ??? ??? ??? ----- +3 -------> HDW GLP VXP ------ + 3 -----> KGZ JOS YAS

You need to do the opposite to go BACK to the original

??? ??? ??? <----- -3 ------- HDW GLP VXP <------ - 3 ----- KGZ JOS YAS

Hint: It's about food.