Given an array A of N integers. The task is to find a peak element in it in O( log N ) .
An array element is peak if it is not smaller than its neighbours. For corner elements, we need to consider only one neighbour.
Note: There may be multiple peak element possible, in that case you may return any valid index (0 based indexing).
Input:
The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. Each test case contains an integer N. Then in the next line are N space separated values of the array.
Output:
For each test case output will be 1 if the index returned by the function is an index with peak element.
User Task:
You don't have to take any input. Just complete the provided function peakElement() and return the valid index.
Expected Time Complexity: O(log N).
Expected Auxiliary Space: O(1).
Constraints:
1 <= T <= 100
1 <= N <= 105
1 <= A[] <= 106
Example:
Input:
2
3
1 2 3
2
3 4
Output:
1
1
Explanation:
Testcase 1: In the given array, 3 is the peak element as it is greater than its neighbour.
Testcase 2: 4 is the peak element as it is greater than its neighbour elements.
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