It must be 33 as the elements in the array sized at 32 are accessed with 0 to 31. If you size it at 32, you will get index out of bounds if a player connects on the last slot (32).
sizing at 33 allows slots of 0 to 32. The first slot of 0 is technically a waste but this required to allow 32 to be a valid slot.
The second part of your example variable is sized at 32 for the max length of a string value.