You're given a sentence and your task is to classify whether the sentence is acceptable or not. Any sentence which is grammatically correct, has a naturalistic text, is written by a native speaker and which minimizes superfluous content is acceptable, otherwise unacceptable. If the sentence is acceptable then write "acceptable", otherwise "unacceptable".

Input: Consider Input: Bob proved that this set is recursive.

Output: acceptable


Input: Consider Input: Ron wanted to wear a tuxedo to the party, but Caspar couldn't decide whether to.

Output: unacceptable


Input: Consider Input: The two boys looked up the high stairs from the floor.


Output: acceptable