shell script question

[Magnus Larsson <knatteman_(_at_)_telia_(_dot_)_com>]

Hello all..

I have a problem in a shellscript...

example.

aa=1
ab=2
ac=3

input=b


what I want is to use variable $input to be part of another variable.

like $a"$input" to refer to the value of $ab, but it doesn't work to 
write like that...
the variable can be in this case a,b or c....

How can i do, will it work in any case???

Hope someone knows howto

Best Regards
//Magnus