17-15-(     )=2

20-5-(     )=11

12-(     )-1=0

14-(     )-3=5

12-3-(     )=7

(     )-6-3=5

18-4-(     )=8

13-9-(     )=3

11-(     )-1=0

15-14-(     )=1

18-4-(     )=9

16-(     )-7=1

(     )-9-0=5

18-(     )-14=2

11-6-(     )=3

11-(     )-0=1

18-(     )-8=0

(     )-4-5=10

16-(     )-2=2

12-(     )-5=7

17-(     )-5=9

(     )-6-7=7

19-(     )-15=4

(     )-1-5=8

15-(     )-1=9

14-(     )-0=11

(     )-18-1=1

14-(     )-6=2

(     )-8-2=1

(     )-7-1=5

(     )-3-0=8

(     )-11-0=1

(     )-11-1=1

13-(     )-6=7

11-5-(     )=2

14-4-(     )=6

11-(     )-10=1

17-1-(     )=4

14-9-(     )=1

(     )-9-1=6

12-10-(     )=1

16-(     )-0=6

12-(     )-6=6

(     )-11-3=6

11-4-(     )=7

19-(     )-7=4

17-(     )-3=9

16-(     )-1=0

14-13-(     )=1

20-18-(     )=1