Binary Search

0Easy

Binary Search

Given a sorted array of integers nums and integer target, return the index of target if found, or -1 if not. Must run in O(log n) time.

Example 1:

Input: nums = [-1,0,3,5,9,12], target = 9 Output: 4

Example 2:

Input: nums = [-1,0,3,5,9,12], target = 2 Output: -1

Example 3:

Input: nums = [5], target = 5 Output: 0

Jnaneshwara Reddy Satti

Builder · ClearCode

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Algorithm Visualizer

O(log 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 search(nums, target):

2 left, right = 0, len(nums) - 1

3 while left <= right:

4 mid = left + (right - left) // 2

5 if nums[mid] == target:

6 return mid

7 elif nums[mid] < target:

8 left = mid + 1

9 else:

10 right = mid - 1

11 return -1

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Binary Search — Easy Binary Search Algorithm | ClearCode