Number of 0 address instructions

Question

How many maximum number of zero address instructions possible?

Answer 1

Now question means we have a computer that supports 0 address and 1 address instructions so no. of 1 address instructions aviliable is 2^4 but we have computer which supports only 14 2 address instructions so unused will be 2^4-2 =2

Now for zero address instruction we will have all the bits as opcode field

Now 14 are used in two address so 2 left now with this no. of two instructions formed will be 2*(2^12)=2^13 zero address instruction possible