package Person ; # package name must be same as file name

sub new{
my $class = shift ;
my ($name, $age) = @_ ;
my $self = {
"name" => $name,
"age" => $age,
    } ;
bless($self, $class) ;
return $self ;
}

sub set_name{
my ($self, $name) = @_ ;
$self->{name} = $name ;
}

sub get_name{
my $self = shift ;
return $self->{name} ;
}

sub set_age{
my($self, $age) = @_ ;
$self->{age} = $age ;
}

sub get_age{
my $self = shift ;
return $self->{age} ;
}

1 ;

use Person ;
package Employee ;

@ISA = qw(Person) ;

sub new{
my $class = shift ;
my ($name, $age, $salary) = @_ ;
my $self = Person->new($name, $age) ;
$self->{salary} = $salary ;
bless($self, $class) ;
return $self ;
}

sub get_salary{
my $self = shift ;
return $self->{salary} ;
}

sub set_salary{
my ($self, $salary) = @_ ;
$self->{salary} = $salary ;
}

sub change_salary{
my $self = shift ;
my $new_salary = shift ;
$self->{salary} = $new_salary ;
}

1 ;

my $employee = Employee->new("zdd", "30", "11k") ;
print $employee->get_name(), "\n" ;
print $employee->get_age(), "\n" ;
print $employee->get_salary(), "\n" ;

# Change age and salary
$employee->set_age(35) ;
$employee->set_salary("20k") ;

# print new info
print $employee->get_name(), "\n" ;
print $employee->get_age(), "\n" ;
print $employee->get_salary(), "\n" ;