Returning the other argument of 2 possible arguments without using conditions [closed]

Simple arithmetic:

return 7 - input + 5;

(which can be simplified as return 12 - input;)

Let’s say the input is 7:

return 7 – 7 + 5 –> return 5

Or if the input is 5:

return 7 – 5 + 5 –> return 7