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(15, 6) :

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