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mediumTwo Pointers

Two Sum II - Input Array Is Sorted

## Problem

Given a **1-indexed** array of integers `numbers` that is already sorted in non-decreasing order, find two numbers such that they add up to a specific `target` number. Let these two numbers be `numbers[index1]` and `numbers[index2]` where `1 <= index1 < index2 <= numbers.length`.

Return the indices of the two numbers, `index1` and `index2`, **added by one** as an integer array `[index1, index2]` of length 2.

The tests are generated such that there is **exactly one solution**. You **may not** use the same element twice.

Your solution must use only constant extra space.

Examples

Input
numbers = [2,7,11,15], target = 9
Output
[1,2]
numbers[1] + numbers[2] = 2 + 7 = 9.
Input
numbers = [2,3,4], target = 6
Output
[1,3]
numbers[1] + numbers[3] = 2 + 4 = 6.
Input
numbers = [-1,0], target = -1
Output
[1,2]
numbers[1] + numbers[2] = -1 + 0 = -1.

Constraints

2 <= numbers.length <= 3 * 10^4 -1000 <= numbers[i] <= 1000 numbers is sorted in non-decreasing order. -1000 <= target <= 1000 The tests are generated such that there is exactly one solution.
Python
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