Easy

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Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number.

The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2.

Note:

• Your returned answers (both index1 and index2) are not zero-based.
• You may assume that each input would have exactly one solution and you may not use the same element twice.

Example:

Input:numbers = [2,7,11,15], target = 9

Output:[1,2]

Explanation:The sum of 2 and 7 is 9. Therefore index1 = 1, index2 = 2.

C++:

/*
 * @Author: SourDumplings
 * @Link: https://github.com/SourDumplings/
 * @Email: changzheng300@foxmail.com
 * @Description: https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/
 * @Date: 2019-04-17 22:37:25
 */

class Solution
{
public:
    vector<int> twoSum(vector<int> &numbers, int target)
    {
        int n = numbers.size();
        vector<int> ret(2);
        for (int i = 0; i < n - 1; i++)
        {
            int thisTarget = target - numbers[i];
            for (int j = i + 1; j < n; j++)
            {
                if (numbers[j] == thisTarget)
                {
                    ret[0] = i + 1;
                    ret[1] = j + 1;
                    return ret;
                }
                else if (numbers[j] > thisTarget)
                {
                    break;
                }
            }
        }
        return ret;
    }
};