I have a question that I can't understand.

Solution said we should iterate x which is the number of subarrays with maximum sums that we will use. But what will we do if we have two subarrays with equal sums?

for example

4 3
-11 16 -11 -1

We will choose 16 for sure. Then we have two options. One is -11 16 and 16 -11 -1, the other is 16 -11 and -11 16 -11 -1. The first one has a better answer.

izban proved that if some pair of subsegments have same sum, it doesn't matter when we choose first $$$k - n$$$ subarrays. But his proof is not correct when we choose $$$ \gt k - n$$$ subarrays.