The room is square. This is because it says "diagonal of the floor..." Which means it is from one corner of the room to the opposite end.
Step-by-step explanation:
It says "four wall room" which means it is a square. It also states that each wall meet at a right angle. To through you off this question stated the word 'diagonal' to mess with you when reading this question quickly. If you look more detailed and I like to re-read sentences in order to recognize all the information given. So the Room IS a Square.
