 Index of first 1 in a sorted array of 0’s and 1’s
##### Submissions: 10840   Accuracy: 48.92%   Difficulty: Basic   Marks: 1

Given a sorted array consisting 0’s and 1’s. The task is to find the index of first ‘1’ in the given array.

Input:
The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. Each test case consists of two lines. First line of each test case contains an Integer N denoting size of array and the second line contains N space separated 0 and 1.

Output:
For each test case, in a new line print the index of first 1. If 1 is not present in the array then print “-1”.

Constraints:
1 <= T <= 100
1 <= N <= 107
0 <= Ai <= 1018

Example:
Input:

2
10
0 0 0 0 0 0 1 1 1 1
4
0 0 0 0

Output:
6
-1

Explanation:
Testcase 1: First index where 1 is presented is 6.

#### ** For More Input/Output Examples Use 'Expected Output' option **

Contributor: Arun Tyagi
Author: arun03

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