Re: Randomly reassign hash keys

[thanos1983]

Hello cormanaz,

Another approach could be:

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %hash = ( "a" => 1,
         "b" => 2,
         "c" => 3,
         "d" => 4
    );

# Export keys from the hash
my @keys = keys %hash;

# Export values from the hash
my @values = values %hash;

my %new_hash;
for ( 0 .. $#keys ) {
    $new_hash{splice @keys, rand @keys, 1} = splice @values, rand @val
+ues, 1;
}

print Dumper \%new_hash;

__DATA__

$ perl test.pl
$VAR1 = {
          'a' => 1,
          'b' => 2,
          'c' => 3,
          'd' => 4
        };

Update:in case that someone is interested in speed simple foreach element loop is always faster. Sample of code:

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
use Benchmark::Forking qw( cmpthese );

my %hash = ( "a" => 1,
         "b" => 2,
         "c" => 3,
         "d" => 4
    );

# Export keys from the hash
my @keys = keys %hash;

# Export values from the hash
my @values = values %hash;

my %new_hash_1;
my %new_hash_2;

cmpthese(100000000, {
    'loop indices' => sub {
    for ( 0 .. $#keys ) {
        $new_hash_1{splice @keys, rand @keys, 1} = splice @values, ran
+d @values, 1;
                }
    },
    'loop elements' => sub {
        for ( @keys ) {
        $new_hash_2{splice @keys, rand @keys, 1} = splice @values, ran
+d @values, 1;
        }
},
     });

__DATA__

$ perl test.pl
                    Rate  loop indices loop elements
loop indices   5211047/s            --          -58%
loop elements 12531328/s          140%

Hope this helps.