Input number 1 determines which bits will be negated in input number 2 ...

Just a note of caution: This phrasing suggests that the order of the operands affects the result of the ^ (bitwise-xor) operator, but it does not. The order is irrelevant:

Win8 Strawberry 5.8.9.5 (32)  Sat 05/28/2022  0:35:22
C:\@Work\Perl\monks
>perl

use strict;
use warnings;

printf "%04b \n", 0b1100 ^ 0b0111;
printf "%04b \n", 0b0111 ^ 0b1100;

^Z
1011
1011
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Update: Slight change to phrasing of first sentence for clarity.