BrainF***- is a BrainF*** derivative that has two more instructions:
|_||Subtracts the current cell from the ce-pointer-plus-oneth cell|
|)||Inverts the current cell, from 0 -> 1+ / 1+ -> 0.|
This lets you compare chars easily:
It also allows for else-if by subtracting, doing a linz (loop if not zero) and inverting a value.
Set the first cell to be the exit value, for example, 65.
Get input, if it's not A, loop. Else, print A a lot of times.