I don't believe in Astrology but it's fun to talk about it.
Here is a simple program written in C that can tell whether you and your friend are compatible or not.
It's a silly program but have fun. :D
Run sandbox.c in a C compiler, such as: https://www.programiz.com/c-programming/online-compiler/
Enter your day of birth, and month of birth, so as your friends also in the same order.