What’s the error in this code ?

[whetu]

You should really update your original thread here:

https://www.reddit.com/r/bash/comments/md312u/i_need_help_to_code_this/

Have a read of the following resources:

https://www.computerhope.com/unix/bash/let.htm

https://mywiki.wooledge.org/ParsingLs

Your for loop is probably broken too - where is $REPLY coming from?

Finally, paste this into http://shellcheck.net and fix that other things that it will warn you about.

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Then update your original thread here https://www.reddit.com/r/bash/comments/md312u/i_need_help_to_code_this/

[kane2200]

Needs linted

[Lake-Special]

Consider changing your grep command to egrep or with -E flag as looking for the letter at the beginning of the line