A bulb company claims that the average lifetime of its bulbs is at least X units.

The company ran a test on N bulbs. You are given the lifetime of N-1 of these bulbs. What is the minimum non-negative integer value of lifetime the remaining bulb can have, such that the claim of the company holds true?

------ Input Format ------

• The first line contains a single integer T - the number of test cases. Then the test cases follow.
• The first line of each test case contains two integers N and X - denoting the number of test bulbs and the minimum average lifetime of bulbs in the company's claim.
• The second line of each test case contains $N - 1 space-separated integers A_{1}, A_{2}, \dots, A_{N-1}$ denoting the lifetimes of N-1 of the test bulbs.

------ Output Format ------

For each testcase, output the minimum non-negative integer value of lifetime the remaining bulb can have such that the claim of the company holds true.

------ Constraints ------

$1 ≤ T ≤ 100$
$2 ≤ N ≤ 100$
$0 ≤ A_{i} ≤ 1000$
$1 ≤ X ≤ 1000$

----- Sample Input 1 ------
3
3 4
1 5
4 2
5 8 6
3 1000
0 0

----- Sample Output 1 ------
6
0
3000

----- explanation 1 ------
Let $Y$ denote the value of the lifetime of the remaining bulb.

Test case 1: The remaining bulb must have lifetime no less than $6$ units. The average lifetime with $Y = 6$ is $\frac{(1+5+6)}{3} = 4 ≥ X$. It can be proven that for any non-negative integer value of $Y < 6$ it is not possible to have an average lifeftime of at least $X = 4$.

Test case 2: The average lifetime with $Y = 0$ is $\frac{(5+8+6+0)}{4} = 4.75 ≥ X$. Thus the minimum non negative value which satisfies the condition is $Y = 0$.

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