#!/usr/bin/env python3

# encoding: utf-8

# author: pyclearl

"""

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.

"""

class Solution:

def twoSum(self, numbers, target):

"""

:type nums: List[int]

:type target: int

:rtype List[int]

>>> s = Solution()

>>> nums = [2, 7, 11, 15]

>>> target = 9

>>> s.twoSum(nums, target)

[1, 2]

Because nums[0] + nums[1] = 2 + 7 = 9,

"""

start = 0

end = len(numbers) - 1

while start < end:

tmp = numbers[start] + numbers[end]

if tmp == target:

return [start + 1, end + 1]

if tmp < target:

start += 1

else:

end -= 1

return []

if __name__ == '__main__':

import doctest

doctest.testmod(verbose=True)