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, 9) :

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		9	1	0	0	1
1	15		9	1	0	0	1	6	0	1	1	1	1	3	10	16	5	8
2	3		9	5	8	0	1	6	1	5	9	5	9	3	14	24	7	12
3	3	↔	3	7	12	5	8	0
4	3	↔	3	7	12	5	8	0
5	3	↔	3	7	12	5	8	0
6	3	↔	3	7	12	5	8	0
7	3		3	5	8	7	12	0
(5)(15) - (8)(9) = 3