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(9, 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
9
14
1
0
0
1
1
14
↔
9
0
1
1
0
5
7
14
10
7
5
2
7
↔
9
7
5
1
0
2
1
8
5
8
5
1
22
14
11
7
3
1
7
11
7
7
5
6
1
18
12
4
3
3
18
12
9
6
4
3
↔
1
9
6
11
7
2
0
20
13
6
4
1
Even
Even
3
2
5
1
↔
1
3
2
11
7
0
6
1
↔
1
3
2
11
7
0
7
1
1
11
7
3
2
0
(11)(9) - (7)(14) = 1