k = 4 = 2^2 (r = 2)
0 0000 A A
1 0001 A A
2 0010 A A
3 0011 A A
4 0100 B B
5 0101 B B
6 0110 B B
7 0111 B B
8 1000 A -> B
9 1001 A -> B
10 1010 A -> B
11 1011 A -> B
12 1100 B -> A
13 1101 B -> A
14 1110 B -> A
15 1111 B -> A
k = 4 = 2^2 (r = 2)
0 0000 0 0
1 0001 0 0
2 0010 0 0
3 0011 0 0
4 0100 1 1
5 0101 1 1
6 0110 1 1
7 0111 1 1
8 1000 0 -> 1
9 1001 0 -> 1
10 1010 0 -> 1
11 1011 0 -> 1
12 1100 1 -> 0
13 1101 1 -> 0
14 1110 1 -> 0
15 1111 1 -> 0