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Thanks, really my bug , found an error - I missed one index

Okay so I tried your code and it seems that for the test case (-y+11)(-55y-6) your answer is y^2-5y-66, which is wrong.
The answer should be 55y^2-599y-66.
I think maybe it's caused by the "-y" in the first bracket which doesn't have a number coefficient?
By the way my test case doesn't include (y-11)(y+6).
Please check your code again and let me know if there are any further problems.

i have the problem with one test case on python
i have this answer y^2-5y-66 but it should be 55y^2-599 y-66
i think it's incorrect case because
My program in case (𝑦−11)(55𝑦+6) got 55y^2-599 y-66
and in case (y-11)(y+6) got y^2-5y-66 and it is correct
Plese check this test case
I've complete all test except this one