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It appears that what you're looking for in the first question is some logic that has the following truth table:

Fixed input, DesiredOutput (another "input"), Other input (actually, truth table output):

0,X,1 (or zero, but I have to choose 1)
1,1,1
1,0,0

That logic could be built with some gates. You could extend this to more levels such as your second question.