hi Mad Mac .... I think this will help you.

#! /usr/bin/perl
use strict ;
use warnings;

my @days=qw(mon tues wed thurs fri sat sun);
my @cols=qw(red orange yellow green blue indigo violet);

foreach (@days ){
     tr/e/E/;
    print "$_\n";
}
foreach (@cols){
    tr/e/E/;
    print "$_\n";
}
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