Find a pair in the array whose sum is equal to the given target

Given an array of sorted numbers and a target sum, find a pair in the array whose sum is equal to the given target.
Write a function to return the indices of the two numbers (i.e. the pair) such that they add up to the given target.

Example 1:
Input: [1, 2, 3, 4, 6], target=6
Output: [1, 3]
Explanation: The numbers at index 1 and 3 add up to 6: 2+4=6

We can use the Two Pointers approach to solve this.

Solution:

Time Complexity:

O(n)

Space Complexity:

O(1)