So in the last contest i.e. Educational round 164 I solved C with the right logic i.e. I was making a new string after the index where n and m have different digits. However initially I set that index to be zero. Now if the latter condition isn't met it adds the whole number twice except the first digits i.e. if the number is 99 and 99 it will give output as 999 & 999 this is a very small bug and can be fixed easily.

was it too hard to put a simple case of n and m being the same? it's not about rating but it hurts when you get the wrong answer in system testing for such a basic test case which I would've presumed is already present.As no one thinks more about the code once it's accepted.

link to the submission 256329939 link to question 1954C - Long Multiplication

Thank you awoo & your co-authors for the contest.

This is truly odd tests, many problems tend to have all possible test cases for relatively small n in pretests (example here would be all valid combination of numbers from 1 to 99)