Leetcode-167. Two Sum II - Input array is sorted

地址：

描述：

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.

给定一个有序整型数组和一个整数 target，在其中寻找两个元素，使其和为 target，返回这两个数的索引。

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.

 

示例：

如: numbers = [2,7,11,15], target = 9
Output: [1,2]
Explanation: The sum of 2 and 7 is 9. Therefore index1 = 1, index2 = 2.
例如：2和7的和是9，返回2、7的所1和2（索引从1开始计算的）

方法：

   public int[] twoSum(int[] numbers, int target) {
        int l = 0;
        int r = numbers.length - 1;
        while (l < r) {
            if (numbers[l] + numbers[r] == target) {
                break;
            } else if (numbers[l] + numbers[r] < target) {
                l++;
            } else {
                r--;
            }
        }

        return new int[]{l + 1, r + 1};

    }