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Easy Accuracy: 52.58% Submissions: 13520 Points: 2

Given a sorted array with possibly duplicate elements. The task is to find indexes of first and last occurrences of an element X in the given array.

Note: If the element is not present in the array return {-1,-1} as pair.

 

Example 1:

Input:
N = 9
v[] = {1, 3, 5, 5, 5, 5, 67, 123, 125}
X = 5
Output:
2 5
Explanation:
Index of first occurrence of 5 is 2
and index of last occurrence of 5 is 5.

Example 2:

Input:
N = 9
v[] = {1, 3, 5, 5, 5, 5, 7, 123, 125}
X = 7
Output:
6 6

 

Your Task:  
You don't need to read input or print anything. Your task is to complete the function indexes() which takes the array v[] and an integer as inputs and returns  the first and last occurrence of the element X. If the element is not present in the array return {-1,-1} as pair.

Can you solve the problem in expected time complexity?


Expected Time Complexity: O(Log(N))
Expected Auxiliary Space: O(1)


Constraints:
1 ≤ N ≤ 105
1 ≤ v[i], X ≤ 1018

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