Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.

Ex Input:
Green energy comes in ____ basic forms.

Ex Output:
two


Ex Input:
International mail consists of ____ categories of mail.

Ex Output:
three


Ex Input:
Viruses are the most common cause of acute asthma episodes in infants ____ months old or younger.

Ex Output:

six