Hi, This one should work fine and detect all "format errors":

for ("2D 3h", "2d", "3h", "3h 2d", "Some string") {
   my ($day, $hour) = map {$_+0} /^(?:(\d+)d\s*)?(?:(\d+)h)?$/i; 
   $day || $hour ? print "Day - $day, hour - $hour\n" : warn "Wrong fo
+rmat $_"
}
[download]

Sincerely, Nikita Savin