# [167\. Two Sum II - Input Array Is Sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/)

:::spoiler Solution

class Solution {
public:
    vector<int> twoSum(vector<int>& numbers, int target)
    {
        int left = 0, right = numbers.size() - 1;
        while (left < right)
        {
            if (numbers[left] + numbers[right] < target) ++left;
            else if (numbers[left] + numbers[right] > target) --right;
            else return vector<int>{left + 1, right + 1};
        }
        return vector<int>{-1, -1};
    }
};

- T: $O(n)$
- S: $O(1)$
:::