Modified version of Two Sum problem

Similar Problems:

- Series: TwoSum Problems & Follow-Up
- CheatSheet: Leetcode For Code Interview
- Tag: #twosum, #twopointer

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. Please note that 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.

Input: numbers={2, 7, 11, 15}, target=9

Output: index1=1, index2=2

Github: code.dennyzhang.com

Credits To: leetcode.com

Hint: Time O(n), Space O(1). Moore voting

Leave me comments, if you have better ways to solve.

## https://code.dennyzhang.com/two-sum-ii-input-array-is-sorted ## Basic Ideas: two pointers. 1. From left to right. 2. From right to left ## Complexity: Time O(n), Space O(1) class Solution(object): def twoSum(self, numbers, target): """ :type numbers: List[int] :type target: int :rtype: List[int] """ index1 = 0 index2 = len(numbers) -1 has_matched = False while index1 < index2: sum_value = numbers[index1] + numbers[index2] if sum_value == target: has_matched = True break elif sum_value > target: index2 -= 1 else: index1 += 1 if has_matched is True: return [index1+1, index2+1] else: return [None, None]