link on problem: 898C - Phone Numbers

I sent this submission 298630099, it didn't pass the 5th test and gave an execution error. This solution 298631384 has passed all the tests, I don't see any differences between them except for the structure of the input data storage, who can tell?

help^-^

I added a lot of problems from the past Codeforces rounds to the mashup, now after adding the tasks I would like to sort them somehow by complexity or even manually drag and drop. Is there an option to do this somehow, or did you initially need to add tasks in the correct sequence?