Description
Given an array of integers nums which is sorted in ascending order, and an integer target, write a function to search target in nums. If target exists, then return its index. Otherwise, return -1. You must write an algorithm with O(log n) runtime complexity.
Examples
Input:
nums = [-1,0,3,5,9,12], target = 9Output:
4Explanation:
9 exists in nums and its index is 4.
Input:
nums = [-1,0,3,5,9,12], target = 2Output:
-1Explanation:
2 does not exist in nums so return -1.
Input:
nums = [5], target = 5Output:
0Explanation:
The only element is 5 at index 0, which matches the target.
Constraints
- •
1 ≤ nums.length ≤ 10⁴ - •
-10⁴ < nums[i], target < 10⁴ - •
All the integers in nums are unique. - •
nums is sorted in ascending order.