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(6, 15) :

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 6 15 1 0 0 1
1 6 15 1 0 0 1 9 3 16 6 8 3
2 3 15 8 3 0 1 12 1 8 4 8 4 6 Even Even 4 2
3 6 3 4 2 8 3 3 3 Even Even 2 1
4 3 3 2 1 8 3 0
5 3 3 2 1 8 3 0
6 3 3 2 1 8 3 0
7 3 3 8 3 2 1 0
(8)(6) - (3)(15) = 3