You want to maximize the profit from a trading portfolio while taking a minimum number of losses.

Given:

• An array pnl of n integers representing monthly profits/losses (negative values are losses)
• An integer k representing the minimum number of losses that must be taken

The traders can:

• Add any positive profit to their profit
• For negative pnl, either subtract it or skip it
• The net profit must always be non-negative

Find the maximum total profit that can be earned after taking at least K losses. Return -1 if it is not possible to take k losses.