That's a job for the all function of List::MoreUtils!

Replace your test by 

if ( all { $serials[0] eq $_ } @serials ) { ...

[download]

PS: I replaced your == test by eq and then you can probably delete the no warnings 'numeric';

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics

In reply to Re: Compare variables when the number of them vary by CountZero
in thread Compare variables when the number of them vary by stroke

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