You are in a party of N people, where only one person is known to everyone. Such a person **may be present** in the party, if yes, (s)he doesn’t know anyone in the party. Your task is to find the stranger (celebrity) in party.

You will be given a square matrix **M** where if an element of row i and column j is set to 1 it means there is an edge from ith person to jth person. An edge represent the relation that i th person knows j th person. You need to complete the function **getId** which finds the id of the celebrity if present else return **-1**. The function getId takes two arguments the square matrix **M** and its size **n**.

**Input:**

The first line of input contains an element T denoting the No of test cases. Then T test cases follow. Each test case consist of 2 lines. The first line of each test case contains a number denoting the size of the matrix M. Then in the next line are space separated values of the matrix M.

** **

**Output:**

For each test case output will be the id of the celebrity if present (0 based index). Else -1 will be printed.

**Constraints:**

1<=T<=60

1<=N<=40

0<=M[][]<=1

**Example:
Input (To be used only for expected output) **

1

3

0 1 0 0 0 0 0 1 0

1

For the above test case the matrix will look like

0 0 0

0 1 0

Here the celebrity is the person with index 1 ie id 1