[167] Two Sum II - Input array is sorted

https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/

• algorithms
• Easy (48.04%)
• Source Code: 167.two-sum-ii-input-array-is-sorted.py
• Total Accepted: 231.4K
• Total Submissions: 463.7K
• Testcase Example: '[2,7,11,15]\n9'

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(object):
    def twoSum(self, numbers, target):
        """
        :type numbers: List[int]
        :type target: int
        :rtype: List[int]
        """
        lenn = len(numbers)

        i, j = 0, lenn-1
        while i < j:
            sm = numbers[i] + numbers[j]
            if sm == target:
                return [i+1, j+1]
            elif sm > target:
                j -= 1
            else:
                i += 1

        return [-1, -1]