I was trying to submit this problem after ensuring the 4 test cases given in the problem, ↵
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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↵
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[My submission](https://codeforces.com/submissions/Qurdestor) ↵
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in the fourth test case ↵
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10 10↵
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10 10↵
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10 10↵
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the answer is -1 and my program actually output -1, but in the submission it said my output is :↵
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8 2↵
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2 0↵
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could anyone explain why !!↵
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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](https://codeforces.com/submissions/Qurdestor) ↵
↵
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 !!↵
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