Amazon Online Assessment (OA) - Connect Ropes

Given n ropes of different lengths, you need to connect these ropes into one rope. You can connect only 2 ropes at a time. The cost required to connect 2 ropes is equal to the sum of their lengths. The length of this connected rope is also equal to the sum of their lengths. This process is repeated until n ropes are connected into a single rope.

Find the minimum possible cost required to connect all ropes.

Input

The input consists of an argument:

ropes: an int array representing the rope length

Output

Return the minimum possible cost required to connect all ropes.

Examples

Example 1:

Input: [8, 4, 6, 12]

Output: 58

Explanation:

The optimal way to connect ropes is as follows

1. Connect the ropes of length 4 and 6 (cost is 10). Ropes after connecting: [8, 10, 12]
2. Connect the ropes of length 8 and 10 (cost is 18). Ropes after connecting: [18, 12]
3. Connect the ropes of length 18 and 12 (cost is 30).

Total cost to connect the ropes is 10 + 18 + 30 = 58

Example 2:

Input: [20, 4, 8, 2]

Output: 54

Example 3:

Input: [1, 2, 5, 10, 35, 89]

Output: 224

Example 4:

Input: [2, 2, 3, 3]

Output: 20

Try it yourself