#P1777. RiverCrossing

RiverCrossing

Afandi is herding N sheep across the expanses of grassland  when he finds himself blocked by a river. Asingle raft is available for transportation.<o:p></o:p>

 

Afandi knows that hemust ride on the raft for all crossings, but adding sheep to the raft makes ittraverse the river more slowly.<o:p></o:p>

 

When Afandi is on theraft alone, it can cross the river in M minutes When the i sheep are added, ittakes Mi minutes longer to cross the river than with i-1 sheep (i.e., total M+M1  minutes with one sheep, M+M1+M2 withtwo, etc.).<o:p></o:p>

 

Determine the minimumtime it takes for Afandi to get all of the sheep across the river (includingtime returning to get more sheep).<o:p></o:p>

Input

On the first line of the input is a single positive integer k, telling the number of test cases to follow. 1 ≤ k ≤ 5 Each case contains:

* Line 1: one space-separated integers: N and M (1 ≤ N ≤ 1000 , 1≤ M ≤ 500).

* Lines 2..N+1: Line i+1 contains a single integer: Mi (1 ≤ Mi ≤ 1000)

Output

For each test case, output a line with the minimum time it takes for Afandi to get all of the sheep across the river.

Sample Input

2    
2 10   
3
5
5 10  
3
4
6
100
1

Sample Output

</p>
18
50

HINT

Source