# What happens to a 32-bit input when a gate will only output 1 bit?

For example, suppose I have a combinational circuit that takes 32 bits as input and outputs 1 bit that is equal to 1 if the 32-bits are equal to 0, and outputs 0 if the 32 bits are anything else. How can I achieve this result using NAND, AND, OR, or inverter gates?

In particular, what happens to the 32 bit result when I put it through a gate. Thus, if I wanted to put the 32 bits in a XOR gate such as:

0       ------------\
XOR -----------
32 bits ------------/


And the output of my combinational circuit was only one bit, what would happen here?

• This smells like homework. – Matt Young Feb 19 '13 at 0:05
• It's actually an old exam question. I couldn't understand the solution, so I was trying to work it through myself. – user19151 Feb 19 '13 at 0:29