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(11, 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
11
14
1
0
0
1
1
14
↔
11
0
1
1
0
3
7
14
12
7
6
2
7
↔
11
7
6
1
0
4
1
8
6
8
6
2
Even
Even
4
3
3
2
7
4
3
7
6
5
1
18
14
9
7
4
1
7
9
7
7
6
6
1
16
13
2
2
3
Even
Even
1
1
5
3
↔
1
1
1
9
7
2
0
10
8
10
8
1
Even
Even
5
4
6
1
↔
1
5
4
9
7
0
7
1
1
9
7
5
4
0
(9)(11) - (7)(14) = 1