#!/usr/bin/perl
use Data::Dumper;
%data = ('Teacher' => 45, 'Doctor' => 40,'Driver' => '10');
if (exists($data{'Plumber'})) {
   print "Number of doctor is $data{'Plumber'}n";
}
else {
    $data{'Plumber'} = 0;
    print "Number of doctor is $data{'Plumber'}n";
}
print Dumper %data;

print "Plumber number: ", ($data{'Plumber'} || 0), "n";

my $value = $data{'Plumber'} // 0;

for my $key (@keys) {
    $data{$key} //= 0;
}

package MyStuff;

sub new {
    my $class = shift;
    my $self = shift;

    return bless $self, $class;
}

sub get {
    my $self = shift;
    my $key = shift;

    return $self->{$key} // 0;
}

my $stuff = MyStuff->new(%data);
my $val = $stuff->get("Plumber");