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(13, 3) :

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	13		3	1	0	0	1
1	13		3	1	0	0	1	10	0	1	1	1	1	5	4	14	2	7
2	5		3	2	7	0	1	2	0	2	8	2	8	1	Even	Even	1	4
3	1		3	1	4	0	1	2	1	1	5	1	5	1	4	18	2	9
4	1	↔	1	2	9	1	4	0
5	1	↔	1	2	9	1	4	0
6	1	↔	1	2	9	1	4	0
7	1		1	1	4	2	9	0
(1)(13) - (4)(3) = 1