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(5, 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 5 15 1 0 0 1
1 5 15 1 0 0 1 10 1 1 1 1 1 5 16 6 8 3
2 5 5 8 3 1 0 0
3 5 5 8 3 1 0 0
4 5 5 8 3 1 0 0
5 5 5 8 3 1 0 0
6 5 5 8 3 1 0 0
7 5 5 1 0 8 3 0
(1)(5) - (0)(15) = 5