Bob is stuck in a dungeon and must break n locks, each requiring some amount of energy to break. The required energy for each lock is stored in an array called strength where strength[i] indicates the energy needed to break the ith lock.

To break a lock, Bob uses a sword with the following characteristics:

Your task is to determine the minimum time in minutes required for Bob to break all n locks and escape the dungeon.

Return the minimum time required for Bob to break all n locks.

 

Example 1:

Input: strength = [3,4,1], k = 1

Output: 4

Explanation:

Time Energy x Action Updated x
0 0 1 Nothing 1
1 1 1 Break 3rd Lock 2
2 2 2 Nothing 2
3 4 2 Break 2nd Lock 3
4 3 3 Break 1st Lock 3

The locks cannot be broken in less than 4 minutes; thus, the answer is 4.

Example 2:

Input: strength = [2,5,4], k = 2

Output: 5

Explanation:

Time Energy x Action Updated x
0 0 1 Nothing 1
1 1 1 Nothing 1
2 2 1 Break 1st Lock 3
3 3 3 Nothing 3
4 6 3 Break 2nd Lock 5
5 5 5 Break 3rd Lock 7

The locks cannot be broken in less than 5 minutes; thus, the answer is 5.

 

Constraints: