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(2, 9) :

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 2 9 1 0 0 1
1 2 9 1 0 0 1 7 1 10 2 5 1
2 1 9 5 1 0 1 8 1 5 2 5 2 4 14 4 7 2
3 4 1 7 2 5 1 3 2 16 4 8 2
4 2 1 8 2 5 1 1 1 Even Even 4 1
5 1 1 4 1 5 1 0
6 1 1 4 1 5 1 0
7 1 1 5 1 4 1 0
(5)(2) - (1)(9) = 1