167. Two Sum II - Input Array Is Sorted

1. TWO POINTER APPROACH

 class Solution {

    public int[] twoSum(int[] numbers, int target) {

        // 1. two pointer approach - initialize the var.

        int left = 0;

        int right = numbers.length-1;

        // 2. while loop until pointers meet

        while(left < right) {

            int currentSum = numbers[left]+numbers[right];

            // 3. check the sum

            if(currentSum == target) {

                return new int[] {left+1, right+1}; // why we did this, Q. asked 1-indexed array, so we add +1 in our 0-idxed array

            } if(currentSum < target) {

                left++;

            } else {

                right--;

            }

        }

        return new int[] {-1, -1}; // -1 cuz exactly 1 solution

    }

   

}

2.

1. TWO POIN1. TWO POINTER APPROACHTER APPROACH