My code is giving "Wrong answer" with "Probably, the solution is executed with error 'uninitialized value usage' on the line 66" as an add up. When I looked for the error, It said my code was returning some value for some test case, but It's not. I don't understand it.

https://codeforces.com/contest/1370/submission/84590348

This is the submission. I would apreciate if someone helped me. If It helps, the question in from round 651 (div 2), question C

Thanks in advance