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

use constant ERR => "Error in program";
use constant OK => "successfully run";

my $failure_status = func(0);
print $failure_status."\n";

my $sucess_status = func(1);
print $sucess_status."\n";


sub func {
 my $error=shift;
 if ($error){
   return ERR;
 }
 else {
   return  OK;
 }
}
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$ perl -l
use strict;
use warnings;

use constant ERR => "Error in program";

sub func {
   return ERR;
}

print func();

__END__
Error in program
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