C. Cherry Bomb
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

Two integer arrays $$$a$$$ and $$$b$$$ of size $$$n$$$ are complementary if there exists an integer $$$x$$$ such that $$$a_i + b_i = x$$$ over all $$$1 \le i \le n$$$. For example, the arrays $$$a = [2, 1, 4]$$$ and $$$b = [3, 4, 1]$$$ are complementary, since $$$a_i + b_i = 5$$$ over all $$$1 \le i \le 3$$$. However, the arrays $$$a = [1, 3]$$$ and $$$b = [2, 1]$$$ are not complementary.

Cow the Nerd thinks everybody is interested in math, so he gave Cherry Bomb two integer arrays $$$a$$$ and $$$b$$$. It is known that $$$a$$$ and $$$b$$$ both contain $$$n$$$ non-negative integers not greater than $$$k$$$.

Unfortunately, Cherry Bomb has lost some elements in $$$b$$$. Lost elements in $$$b$$$ are denoted with $$$-1$$$. Help Cherry Bomb count the number of possible arrays $$$b$$$ such that:

  • $$$a$$$ and $$$b$$$ are complementary.
  • All lost elements are replaced with non-negative integers no more than $$$k$$$.
Input

The first line of the input contains a single integer $$$t$$$ ($$$1 \le t \le 10^4$$$) — the number of test cases.

The first line of each test case contains two integers $$$n$$$ and $$$k$$$ ($$$1 \le n \le 2 \cdot 10^5$$$, $$$0 \le k \le 10^9$$$) — the size of the arrays and the maximum possible value of their elements.

The second line contains $$$n$$$ integers $$$a_1, a_2, ..., a_n$$$ ($$$0 \le a_i \le k$$$).

The third line contains $$$n$$$ integers $$$b_1, b_2, ..., b_n$$$ ($$$-1 \le b_i \le k$$$). If $$$b_i = -1$$$, then this element is missing.

It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$2 \cdot 10^5$$$.

Output

Output exactly one integer, the number of ways Cherry Bomb can fill in the missing elements from $$$b$$$ such that $$$a$$$ and $$$b$$$ are complementary.

Example
Input
7
3 10
1 3 2
-1 -1 1
5 1
0 1 0 0 1
-1 0 1 0 -1
5 1
0 1 0 0 1
-1 1 -1 1 -1
5 10
1 3 2 5 4
-1 -1 -1 -1 -1
5 4
1 3 2 1 3
1 -1 -1 1 -1
5 4
1 3 2 1 3
2 -1 -1 2 0
5 5
5 0 5 4 3
5 -1 -1 -1 -1
Output
1
0
0
7
0
1
0
Note

In the first example, the only way to fill in the missing elements in $$$b$$$ such that $$$a$$$ and $$$b$$$ are complementary is if $$$b = [2, 0, 1]$$$.

In the second example, there is no way to fill in the missing elements of $$$b$$$ such that $$$a$$$ and $$$b$$$ are complementary.

In the fourth example, some $$$b$$$ arrays that are complementary to $$$a$$$ are: $$$[4, 2, 3, 0, 1], [7, 5, 6, 3, 4],$$$ and $$$[9, 7, 8, 5, 6]$$$.