20-20=

13-6=

20-15=

17-8=

16-3=

16-12=

17-2=

15-2=

11-10=

17-8=

12-7=

11-8=

19-4=

20-18=

20-5=

20-11=

14-4=

16-11=

19-4=

16-12=

15-1=

18-15=

20-14=

12-12=

11-9=

11-10=

11-6=

16-5=

16-2=

18-2=

13-0=

14-8=

18-3=

12-1=

15-2=

13-4=

20-11=

13-8=

19-9=

16-0=

16-5=

11-1=

16-13=

19-13=

18-6=

11-5=

20-11=

19-7=

20-10=

13-0=