Two Sum II Sorted Array

1Medium

Two Sum II Sorted Array

Given a 1-indexed sorted array of integers, find two numbers that add up to target. Return their 1-based indices. Use O(1) extra space.

Example 1:

Input: numbers = [2,7,11,15], target = 9 Output: [1,2]

Example 2:

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

Example 3:

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

Jnaneshwara Reddy Satti

Builder · ClearCode

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Algorithm Visualizer

O(N)

Before starting this video, please check the description to ensure you know the prerequisites. If you're comfortable with arrays and hash maps, let's go!

TEST CASE: []O(1)

clearcode.in

Execution Trace

1def two_sum(numbers, target):

2 left = 0

3 right = len(numbers) - 1

4 while left < right:

5 current_sum = numbers[left] + numbers[right]

6 if current_sum == target:

7 return [left + 1, right + 1]

8 elif current_sum < target:

9 left += 1

10 else:

11 right -= 1

12 return []

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Two Sum II Sorted Array — Medium Two Pointers Algorithm | ClearCode