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:
Most healthy men experience about three to ____ erections in their sleep each night.

Ex Output:
five


Ex Input:
Most ducks acquire breeding plumage in the fall, ____ or seven months before other birds.

Ex Output:
six


Ex Input:
Normal bone has ____ layers.

Ex Output:

two