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.

Input: Consider Input: Blisters normally burst and crust over within three to ____ days.

Output: five


Input: Consider Input: Copper has ____ naturally occurring isotopes.

Output: two


Input: Consider Input: Cnidarians have ____ forms.


Output: two