2838. Maximum Coins Heroes Can Collect

If a hero can defeat the ith monster, then he defeats all the monsters having a power less than monster[i].

Sort monsters by their powers. Also change the order of the coins array according to this sort.

Construct a prefix sum array for the updated coins array.

For each hero, do a binary search and find the last position of the most powerful monster that this hero can defeat.

If said monster has index i, then the ith element of the partial sum array would be the answer.