Given a sorted array having N elements, find the indices of the first and last occurrences of an element X in the given array.
Note: If the number X is not found in the array, return '-1' as an array.
Example 1:
Input:
N = 4 , X = 3
arr[] = { 1, 3, 3, 4 }
Output:
1 2
Explanation:
For the above array, first occurence
of X = 3 is at index = 1 and last
occurence is at index = 2.
Example 2:
Input:
N = 4, X = 5
arr[] = { 1, 2, 3, 4 }
Output:
-1
Explanation:
As 5 is not present in the array,
so the answer is -1.
Your Task:
You don't need to read input or print anything. Complete the function firstAndLast() that takes the array arr, its size N and the value X as input parameters and returns a list of integers containing the indices of first and last occurence of X.
Expected Time Complexity: O(log(N))
Expected Auxiliary Space: O(1)
Constraints:
1 <= N <= 10^5
0 <= arr[i], X <= 10^{9}

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