# 167. Two Sum II - Input Array Is Sorted 两数之和 II - 输入有序数组

@TOC

## # 题目描述

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.

Note:

• 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.
``````

## # 解题方法

### # Java解法

``````public class Solution {
public int[] twoSum(int[] numbers, int target) {
int index[] = new int[2];
int left = 0;
int right = numbers.length - 1;
while(left < right){
long temp = numbers[left] + numbers[right];
if(temp == target){
index[0] = left + 1;
index[1] = right + 1;
break;
}else if(temp < target){
left++;
}else{
right--;
}
}
return index;
}
}
``````

### # Python解法

``````class Solution:
def twoSum(self, numbers, target):
"""
:type numbers: List[int]
:type target: int
:rtype: List[int]
"""
N = len(numbers)
left, right = 0, N - 1
while left < right:
cursum = numbers[left] + numbers[right]
if cursum == target:
return [left + 1, right + 1]
elif cursum < target:
left += 1
else:
right -= 1
return [0, 0]
``````

## # 日期

2017 年 4 月 18 日 2018 年 11 月 14 日 —— 又到周五了