X = 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
Y = 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
X ↔ Y

Ext-GCD(12, 7) :

i GCD Bezout AOdd : AEven :
A B ax ay bx by |A-B| A↔B Sx Sy ax
Sx'
ay
Sy'
A
A/2
ax
ax + Y
ay
ay + X
ax
ax/2
ay
ay/2
0 12 7 1 0 0 1
1 12 7 1 0 0 1 5 6 8 12 4 6
2 6 7 4 6 0 1 1 3 Even Even 2 3
3 3 7 2 3 0 1 4 1 2 4 2 4 2 Even Even 1 2
4 2 3 1 2 2 3 1 1 8 14 4 7
5 1 3 4 7 2 3 2 1 6 10 6 10 1 Even Even 3 5
6 1 1 3 5 4 7 0
7 1 1 3 5 4 7 0
(3)(12) - (5)(7) = 1