I was trying to submit this problem after ensuring the 4 test cases given in the problem,

but I found it gives wrong answer in test 4, even this test case I try to run it, and it gives the correct answer

My submission

in the fourth test case

10 10

10 10

10 10

the answer is -1 and my program actually output -1, but in the submission it said my output is :

8 2

2 0

could anyone explain why !!