use strict;
use warnings;
use Data::Dump qw(dump);


#my @t = ( {'b','1','w','10'},{'b','3','w','30'},{'b','2','w','40'});
# at first, making hash readable as such
my @t = ( {'b' => '1','w' => '10'},{'b' => '3','w' =>'30'},{'b' => '2','w' => '40'});
# consider issue: the value in key 'b' is numeric, use spaceship '<=>' for compare

# transform by Randal Schwartz
@t = 
	map{$_->[0]}
	sort{$a->[1] <=> $b->[1]}
	map{ [$_, $_->{b}] }@t;

print dump \@t;