Merge elements

Given an integer array A of size N. You have to merge all the elements of the array into one with the minimum possible cost.

The rule for merging is as follows:

Return the minimum possible cost of merging all elements.

1 <= N <= 200

1 <= A[i] <= 10³

First and only argument is an integer array A of size N.

Return an integer denoting the minimum cost of merging all elements.

Input 1:

 A = [1, 3, 7]

Input 2:

 A = [1, 2, 3, 4]

Output 1:

 15

Output 2:

 19

Explanation 1:

 All possible ways of merging:
 a) {1, 3, 7} (cost = 0) -> {4, 7} (cost = 4) -> {11} (cost = 4+11 = 15)
 b) {1, 3, 7} (cost = 0) -> {1, 10} (cost = 10) -> {11} (cost = 10+11 = 21)
 Thus, ans = 15