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: Most children start primary school at ____ years of age.

Output: five


Input: Consider Input: Water consists of ____ hydrogen and one oxygen atom.

Output: two


Input: Consider Input: Water dissolves about one part in ____ thousand parts, and receives a brown color.


Output: seven