If you look through my posts in this thread, you'll see:

"Please show actual output between <code>...</code> tags."

"Please also show expected output (again, between <code>...</code> tags)."

"... two polite requests to use "<code>...</code> tags" for showing output, ..."

In each of those I'm making reference to output.

Now you write:

"Thanks for the response but if you see my code I pasted my code between ."

Here you're referring to code not output. [Side issue: You've failed to finish that sentence.]

And then you write:

"I don't know why are you saying unreadable mess"

That would be this:

"Thanks for the response Ken. I have tried 3 ways but all of them throwing error: 1). As suggested: @{$difference[0]} Error -- >Can't use string ("ARRAY(0x2c992e0)") as an ARRAY ref while "strict refs" in use at 2). Tried 2nd way @{$difference} Error as below -- > Global symbol "$difference" requires explicit package name at Global symbol "$intersect" requires explicit package name at Global symbol "$union" requires explicit package name at . 3). tried 3rd way @difference DEBUG: - difference links values ARRAY(0x32690e0) ARRAY(0x3269090) ARRAY(0x322d040) ARRAY(0x3276990) ARRAY(0x322d060) ARRAY(0x3269f80) ARRAY(0x3269040) DEBUG: - intersect links values DEBUG: - union links values ARRAY(0x32690e0) ARRAY(0x3269090) ARRAY(0x322d040) ARRAY(0x3276990) ARRAY(0x322d060) ARRAY(0x3269f80) ARRAY(0x3269040) Expected output should be device names(e.g ..ABC-DCFE41->90) so that I can remove difference part one by one from the data set."

I made all sorts of allowances for this being your first post here. I made polite requests, explained the reasoning behind those requests, provided examples and pointed you to further information. Yes, you do "appear to have completely ignored me".