Help creating an asterisk and T diamond

[ibreeden]

Is that a diamond? It looks like a diabolo to me. I would draw a diamond like this:

Output:
****/\****
***/TT\***
**/TTTT\**
*/TTTTTT\*
/TTTTTTTT\
\TTTTTTTT/
*\TTTTTT/*
**\TTTT/**
***\TT/***
****\/****

One can still argue it this resembles a diamond, but at least it resembles a diamond in playing cards.

You have to split your assignment in several parts. From what you show us the first part is about inputting values. The input values should be checked and while the check fails, the user should be asked again for the correct input value.
Show us how you solve this. Then we can continue with the computation part.