Select Code to Download

my $key1 = '00001';
my $key2 = 1;
...
   $hash3{$key1} = 3;
my %hash4;
   $hash4{$key2} = 4;

00001 == 1       That is: $key1 == $key2
00001 ne 1       That is: $key1 ne $key2
...
$hash3{$key2} is undef
$hash4{$key1} is undef
$hash4{$key2} == 4