If you are in a completley empty room with only a cylinder f

If you are in a completley empty room with only a cylinder full of water, how do you determine the amount of water? I am looking for a creative response to this question, thanks!

Solution

Tilt the cylinder which is initially full of water, and now slowly pour the water on ground.

the first time when the surface of the water touches the base of cylinder, stop pouring.

Now the remaining water will be exactly half of the initial amount.

So if initial amount of water = V

then amount of water after this procedure will be = V/2

Let me know in the comments if you have any doubt.