Shell Programming and Scripting

i cant get around using regular expressions in if/else statements. it simply doesnt give me the right results.

i've tried using switch/case but that is just as sh!tty as well. (pardon my french but im getting frustrated with c shell..only reason why im writing in it is because it's a hwk assignment to compare bourne with c shell)

anyways
im trying to write a regular expression that says a string must begin with A have any number of [d-f] in between and end with B

so what i got is basically this..

=========

echo -n "Enter a string: "

set $string = $<

if ($string =~ '^A[d-f]*B$') then
echo "accepted"
else
echo "rejected"
endif

exit
==========

it simply doesnt work

cshell doesnt seem to like the anchors or other special characters.

any feedback would be greatly appreciated.

Please read the Rules about homework assignments. Thanks.

sorry. however, that piece of code is just 5% of my assignment as a whole. and i'm not posting my assignment and asking somebody to do it for me, i have something and i'm asking for advise on how to get it to work. i cant see how most ppl in here arent asking questions related to their assignments.

....'cause the rules are eing enforced?
I don't know......

here's something to start with.......

Code:

#!/bin/ksh

a='AdeffedB'

if [[ $(expr  "$a" :  '^A[d-f][d-f]*B$') -ne 0 ]]; then
   echo 'found'
else
   echo 'NOT found'
fi