sub recursive_mult_by_100() {
  if (!ref) { $_ *= 100 }
  elsif (ref eq 'ARRAY') { recursive_mult_by_100 for @$_ }
  elsif (ref eq 'HASH') { recursive_mult_by_100 for values %$_ }
  else { die "Unhandled data type ".ref; }
}

recursive_mult_by_100 for $deep;