Premium Batch Shipping

A logistics company ships items in batches of a fixed size W. Each item has a shipping cost. A batch is considered 'Premium' if it contains no more than E items with a cost strictly greater than threshold T. Find the maximum total cost of any valid Premium batch. Input Format: - The first line contains four integers: W (batch size), E (max premium items), T (cost threshold), and N (total items). - The second line contains N space-separated integers representing the costs of the items in order. Output Format: - Print the maximum sum of a valid batch. If no batch is valid, print -1. Example: Input: 3 1 10 5 5 12 15 7 8 Output: 30 Explanation: Window [15, 7, 8] has sum 30 and only one item (15) > 10. Window [5, 12, 15] is invalid because it has two items > 10.