Put Marbles in Bags Python Solution with Tests

lcpy gen -n 2551   # by problem number
lcpy gen -s put_marbles_in_bags   # by problem name

Input: weights = [1,3,5,1], k = 2
Output: 4
Explanation:
The distribution [1],[3,5,1] results in the minimal score of (1+1) + (3+1) = 6.
The distribution [1,3],[5,1], results in the maximal score of (1+3) + (5+1) = 10.
Thus, we return their difference 10 - 6 = 4.

Input: weights = [1, 3], k = 2
Output: 0
Explanation: The only distribution possible is [1],[3].
Since both the maximal and minimal score are the same, we return 0.

class Solution:
    # Time: O(n log n)
    # Space: O(n)
    def put_marbles(self, weights: list[int], k: int) -> int:
        if k == 1:
            return 0
        pair_sums = sorted(weights[i] + weights[i + 1] for i in range(len(weights) - 1))
        splits = k - 1
        return sum(pair_sums[-splits:]) - sum(pair_sums[:splits])