I live in a flat. My block consists of three staircases.
The flats are numbered. Number one is the primary number.
The staircases are labelled A, B and C.
Each staircase consists of nine flats. The block has got three floors.
When you enter each floor you see one flat is on the left, one is on the right, one is in the middle.
There is only one flat in the exact center of the block. It is mine.
The flat entity is 9 X 3. There is no repetition in the number of the flats.
Where do I live?