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, 14) :
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
14
1
0
0
1
1
14
↔
5
0
1
1
0
9
7
14
6
7
3
2
7
↔
5
7
3
1
0
2
0
8
3
8
3
1
22
8
11
4
3
1
↔
5
11
4
1
0
4
1
12
4
12
4
2
Even
Even
6
2
4
2
1
6
2
11
4
1
1
Even
Even
3
1
5
1
1
3
1
11
4
0
6
1
1
3
1
11
4
0
7
1
1
3
1
11
4
0
(3)(5) - (1)(14) = 1