About computer essential

We can examine an algorithm to generate the 2s Complement of an integer (flip all bits; add 1).

We also saw how any number in binary can be directly represented in hex(ie. 3=0010, B=1011, A =1010, D=1101)

Putting the above two together, work out an algorithm in words that takes a number in hex and directly obtains its 2s Complement representation in hex (e.g. 0xBEEF 0x4111).

Justify your answer - i.e. give reason(s) why your algorithm works correctly.