Greedy for Min/Max Objectives

Pair sorting with prefix sums or two-pointer after greedy assignment.

Try this in Python

vals = [4, 1, 3]
vals.sort()
print(sum(vals[i] * (i + 1) for i in range(len(vals))))

Key takeaways

• Exchange proof often swaps adjacent inverted pair.
• For min-cost flow-like problems greedy may fail—recognize structure.
• Check integer overflows in products.