Hello. I am trying to submit my solution, which works on my machine but when I run on the codeforces engine a runtime error is presented the following message is shown: Probably, the solution is executed with error 'uninitiaized value usage' on the line 28. The link for the code follows: https://ideone.com/ZE2U7l I really cannot see why this error is happening.

EDIT 1: Here is the link of the question: https://codeforces.me/contest/1312/problem/C