Why not all test cases passed?
link doesn’t contain any code
at line no 20
b[(sum+n)%n]++;
this is not correct because if sum and n both large then it overflow and give run time error
what you have to do is use this
b[((sum%n)+n)%n]++;
after that all testcase get passed
Modified Code
if you want to ask something about this feel free to ask
i hope this helps
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