Battleship#1476
Parallel to the coastline, an enemy fleet is stationed at sea. The area where the fleet is located is divided into squares. On the main ship of our fleet, there is a secret weapon that can strike consecutive squares simultaneously. All enemy ships within these targeted squares will be destroyed. Unfortunately, the secret weapon can only be used once, so it is crucial to maximize the damage inflicted on the enemy with this single shot.
Write a program to determine the maximum number of ships that can be destroyed with one shot.
The first line contains two integers and (1 \leq k \leq n \leq 10^5). The second line contains integers a_{i} (0 \leq a_i \leq 10000), where each integer represents the number of ships in the corresponding square of the strip.
Output the maximum number of ships that can be destroyed.
Example 1