Two Sum II - Input array is sorted

Two Sum II - Input array is sorted.cpp

/*
167. Two Sum II - Input array is sorted
Easy



Given an array of integers numbers that is already sorted in non-decreasing order,
find two numbers such that they add up to a specific target number.

Return the indices of the two numbers (1-indexed) as an integer array
answer of size 2, where 1 <= answer[0] < answer[1] <= numbers.length.

The tests are generated such that there is exactly one solution.
You may not use the same element twice.

 

Example 1:

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.
Example 2:

Input: numbers = [2,3,4], target = 6
Output: [1,3]
Example 3:

Input: numbers = [-1,0], target = -1
Output: [1,2]

*/
class Solution {
public:
    vector<int> twoSum(vector<int>& numbers, int target) {
        int end=numbers.size()-1, start=0;
         vector<int> ans;
        while(end>start)
        {
            if(numbers[end]+numbers[start]==target)
            {ans.push_back(start+1);ans.push_back(end+1);return ans;}
            else if(numbers[end]+numbers[start]<target)
                     start++;
               else
                   end--;
            
            
        }
        return ans;
    }
};