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: Cytochrome oxidase consists of two cytochromes and ____ copper atoms.

Output: two


Input: Consider Input: Most people get one or ____ common colds every year.

Output: two


Input: Consider Input: Most insects have ____ antennae, six legs, and four wings.


Output: two