Subarray Squares

Given an array of n elements, your task is to divide into k subarrays. The cost of each subarray is the square of the sum of the values in the subarray. What is the minimum total cost if you act optimally? Input The first input line has two integers n and k: the array elements and the number of subarrays. The array elements are numbered 1,2,\dots,n. The second line has n integers x_1,x_2,\dots,