Convert multilevel hash in simple hash in perl -

i have hash multilevel hash want convert single level .but not able that

actual hash:

'mainslab' => {                 'a1' => {                            'slab' => {                                      '49_168' => {                                                    'amt' => '3000',                                                    'start' => '49',                                                    'end' => '168'                                                  },                                      '169_720' => {                                                     'amt' => '3000',                                                     'start' => '169',                                                     'end' => '720'                                                   },                                      '2_48' => {                                                  'amt' => '3000',                                                  'start' => '2',                                                  'end' => '48'                                                },                                      '721_-' => {                                                   'amt' => '3000',                                                   'start' => '721',                                                   'end' => '-'                                                 }                                 }                          },                      'a2' => {                        'slab' => {                                  '49_168' => {                                                'amt' => '3000',                                                'start' => '49',                                                'end' => '168'                                              },                                  '169_720' => {                                                 'amt' => '4000',                                                 'start' => '169',                                                 'end' => '720'                                               },                                  '2_48' => {                                              'amt' => '5000',                                              'start' => '2',                                              'end' => '48'                                            },                                  '721_-' => {                                               'amt' => '3000',                                               'start' => '721',                                               'end' => '-'                                             }                             }                      }               } 

i want convert simple , single level hash :

slab =>{                 "49_168"=>{"a1"=> "3000","a2"=>"3000"},                 "169_720"=>{"a1"=>"4000","a2"=>"4000"},                 "2_48"=>{"a1"=>"5000","a2"=>"5000"},                 "721_"=>{"a1"=>"3000","a2"=>"3000"}         } 

please me how can this

assuming

my %hash = (     'mainslab' => {                 'a1' => {                            'slab' => {                                        '49_168' => {                                                'amt' => '3000',                                                'start' => '49',                                                'end' => '168'                                              },                  'a2' => ... );   

then:

my $hashref     = $hash{'mainslab'}; $new_hashref = {}; foreach $ax (keys %$hashref) {    foreach $k (keys %{$hashref->{$ax}{'slab'}}) {      $new_hashref->{$k}{$ax} = $hashref->{$ax}{'slab'}{$k}{'amt'};    } } %new_hash    = (slab => $new_hashref); 

will produce:

$new_hash = ( 'slab' => {                  '49_168' => {                         'a1' => '3000',                         'a2' => '3000'                       },                  '169_720' => {                          'a1' => '3000',                          'a2' => '4000'                  ...            );