Someone who knew me well enough to use my own words and personal code.

I think we actually have to be at war with something to use a higher code.

But he would reach them by using various codes from the past.

I gave up on trying to use other people's code after several bad experiences.

I'm sure these guys will be using code or such to report their progress home.

For example, 1+3 and 6-2 both achieve the same result while using different code.

She opens the door using a code from the book.

"Use his code if you want to speak to us."

For example, 3+1 and 6-2 both achieve the same result, yet use completely different code.

It is also possible to use multiple codes at once.