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Pair with Target Sum (easy)

## Problem Statement

Given an array of numbers sorted in ascending order 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. If no such pair exists return [-1, -1].

**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
```

**Example 2**:

```
Input: [2, 5, 9, 11], target=11
Output: [0, 2]
Explanation: The numbers at index 0 and 2 add up to 11: 2+9=11
```

**Constraints:**

- 2 <= arr.length <= 10<sup>4</sup>
- -10<sup>9</sup> <= arr[i] <= 10<sup>9</sup>
- -10<sup>9</sup> <= target <= 10<sup>9</sup>
- Only
`one`

valid answer exists.

## Try it yourself

Try solving this question here:

Python3

Python3

. . .

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