Can anyone explain the approach used by neal to solve the problem 'Carrying Conundrum' from Codeforces Round #742 (Div. 2) here is the submission link https://codeforces.com/contest/1567/submission/127953876 I have used my full potential to understand this approach, but i am still not able to figure it out. Plz help Thank You

Here are my two submissions https://codeforces.com/contest/1484/submission/110870622 when i change ceil(m/2) with (m+1)/2 it got AC https://codeforces.com/contest/1484/submission/110882130 But i think ceil(m/2) and (m+1)/2 give same result... I can not figure out the reason.. Can anyone help? Any help would be highly appreciated... Thank You.

https://codeforces.com/contest/1486/submission/108784497 This is my submission for C2 problem of round #703 it is giving me WA on test case 3 and i am not able to figure it out Can Anyone Help? It would be highly appreciated.

https://codeforces.com/contest/20/submission/105231894
I am Implementing the soln above But i am getting MLE(it is totally unexpected) I can not figure out when i see others code of same problem they have done exactly same thing and they get AC but i am getting MLE https://codeforces.com/contest/20/submission/105228166(watch this) please help|