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, 12) :

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