力扣167. 两数之和 II - 输入有序数组

 每次固定一个数，再二分搜另一个数即可。

class Solution {
public:
    vector<int> numbers;
    int binaryFind(int left, int right, int key) {
        if (left > right) {
            return -1;
        }
        int mid = (left + right) / 2;
        if (numbers[mid] == key) {
            return mid;
        }
        if (numbers[mid] > key) {
            return binaryFind(left, mid - 1, key);
        }
        if (numbers[mid] < key) {
            return binaryFind(mid + 1, right, key);
        }
        return -1;
    }
    vector<int> twoSum(vector<int>& numbers, int target) {
        this -> numbers = numbers;
        for (int i = 0; i < numbers.size(); ++i) {
            int other_target = target - numbers[i];
            int res = binaryFind(0, numbers.size() - 1, other_target);
            if (res != -1 && res != i) {
                return {min(i + 1, res + 1), max(i + 1, res + 1)};
            }
        }
        return {};
    }
};