use warnings;

%h = ( '512_x64' => '24', 'world' => 'hello');

print $h{world}, "\n";   # line 5
print $h{512_x64}, "\n"; # line 6

##</code><code>##

Misplaced _ in number at try.pl line 6.
hello
Use of uninitialized value in print at try.pl line 6.