Binary Search
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.
Example 1
Input
nums = [-1,0,3,5,9,12], target = 9Output
49 exists in nums and its index is 4.
Example 2
Input
nums = [-1,0,3,5,9,12], target = 2Output
-12 does not exist in nums so return -1.
Constraints
- 1 <= nums.length <= 10^4
- -10^4 < nums[i], target < 10^4
- All the integers in
numsare unique. numsis sorted in ascending order.