Given two sorted arrays. There is only 1 difference between the arrays. First array has one element extra added in between. Find the index of the extra element.

**Input:**

The first line of input contains an integer T, denoting the no of test cases. Then T test cases follow. The first line of each test case contains an integer N, denoting the number of elements in array. The second line of each test case contains N space separated values of the array A[]. The Third line of each test case contains N-1 space separated values of the array B[].

**Output:**

Return the index of the corresponding extra element in array A[].(starting index 0).

**Constraints:**

1<=T<=100

1<=N<=100

1<=Ai<=1000

**Example:**

**Input:**

2

7

2 4 6 8 9 10 12

2 4 6 8 10 12

6

3 5 7 9 11 13

3 5 7 11 13

**Output:**

4

3