12-2=
11-8=
7+5=
6+7=
13-4=
16-9=
15-7=
17-8=
5+9=
14+5=
10+10=
18-0=
15-8
A.17-10
14-6
B.11-2
18-9
C.16-8
16-9= 17-8= 15-7= 11-4= 3+9=
14-6= 5+9= 12-5= 4+9= 12-3=
(从12-6开始,按 方向计算)