#!/usr/bin/perl
use strict;

my %position;
my @data = ( qw[orange strawberry apple orange banana orange apple coc
+onut] );

my $pos = -1;
foreach my $item (@data) {
    ++$pos;
    push (@{$position{$item}}, $pos);
}

foreach my $foo (keys %position) {
    if (scalar @{$position{$foo}} > 1) {
        print "$foo occurs on positions @{$position{$foo}}\n";
    }
}


__OUTPUT__
apple occurs on positions 2 6
orange occurs on positions 0 3 5
END__OUTPUT__
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