use warnings;
use strict;
use Data::Dumper;
my @vals = qw( 1 2 3 1 3 3 3 43 bob 2 bob 6 2 );
my %freqs;

$freqs{$_}++ foreach @vals;

my @sorted = map  { $_->[0] }
             sort { $a->[1] <=> $b->[1] }
             map  { [ $_, $freqs{ $_ } ] } keys %freqs;

print Dumper( \@sorted );