A quick lesson on: What is IMP?

[SMcNeill]

One way to break down the logic of IMP is to remember with A IMP B:

Your result is *always* going to have all the bits of B set…

For example, let’s assume A and B are both _UNSIGNED _BYTEs.

Now if B =3, the result of A IMP B will be = ??????11, depending on A to fill in the ?
And if B = 5, the result of A IMP B will be = ?????1?1, depending on A to fill in the ?

*Whatever* the final result is, it’s going to have every bit set that B already has set.

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And, with that half of the process solved, it’s *also* going to set any bits that A *DOES NOT* have set.

A = 2.  B = 3.

In binary, those are:
A = 00000010
B = 00000011

A IMP B is solved by first setting all the bits in the answer to match B:   ??????11
Then we toggle all the bits in A: 11111101.
And we set the ones that are on, for our answer: 11111111

2 IMP 3 = 255

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(NOT A) OR B

That’s the breakdown of what IMP is doing.

(NOT A) says the result is going to have all the bits set that A does NOT have.
OR B says our result is *also* going to have all the bits set that B does.

A IMP B = (NOT A) OR B

Really, that’s all there is to it.  It’s convoluted, and not really something I think most folks ever really need, but that’s all the does in a nutshell.