15-10=

12-5=

20-10=

12-9=

16-9=

14-11=

13-7=

19-15=

20-13=

17-7=

20-17=

12-5=

17-7=

20-18=

13-11=

15-10=

12-0=

19-3=

17-16=

17-10=

11-4=

11-9=

16-1=

13-5=

17-7=

15-13=

11-7=

19-19=

11-10=

20-5=

20-1=

19-4=

13-1=

16-10=

18-16=

13-13=

13-13=

20-17=

18-9=

14-11=

17-3=

19-6=

11-1=

15-5=

14-13=

16-12=

16-6=

16-12=

16-9=

19-2=