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, 2) :

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 2 1 0 0 1
1 2 7 0 1 1 0 5 1 2 8 1 4
2 1 7 1 4 1 0 6 1 2 4 2 4 3 Even Even 1 2
3 3 1 1 2 1 4 2 0 2 6 2 6 1 Even Even 1 3
4 1 1 1 3 1 4 0
5 1 1 1 3 1 4 0
6 1 1 1 3 1 4 0
7 1 1 1 3 1 4 0
(1)(7) - (3)(2) = 1