Contest Link : https://www.codechef.com/HOCO2020/

First problem could be done using strings…

How did you guys solve 2nd and 3rd one ?

I used prefix sums in 3rd one which fortunately worked out(AC) and thought something for 2nd which turned out to be wrong(WA) So, how do we determine who wins the game in 2nd problem ?

Edit:- Realized the basic xor nim was the answer for the 2nd problem which I completely ignored , but it is not that easy/straightforward as mentioned by