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(7, 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 7 15 1 0 0 1
1 7 15 1 0 0 1 8 1 1 1 1 1 4 16 8 8 4
2 4 7 8 4 1 0 3 2 Even Even 4 2
3 2 7 4 2 1 0 5 1 Even Even 2 1
4 1 7 2 1 1 0 6 1 3 1 3 1 3 18 8 9 4
5 3 1 9 4 2 1 2 0 11 5 11 5 1 26 12 13 6
6 1 1 13 6 2 1 0
7 1 1 13 6 2 1 0
(13)(7) - (6)(15) = 1