tell me somebody please what in this test?

Don't know what's in this test but try these ones:

2 7
2 -1
> Impossible

2 -7
-6 3
> Impossible

1 1000
-1000
> 1000 3000

1 -1000
1000
> 3000 1000

1 -999
999
> 2997 999

:( my program works perfectly about all these tests but still have WA on test 7..