Can anyone tell me what is the error in this script

I wouldn't like to convey the impression of bashing you by posting a separate "answer" to your post, but I most definitely want to stress that to answer you actual question above, there are far too many errors in "this script" (it's not even a script, FWIM) to point them out all.

Actually, taking into account how short it is, it could easily score a very high rating for the density of errors it exhibits. Both in logic and in syntax. It doesn't even compile. Maybe it's valid code. Just not perl code. Period.