Binary Search
Detailed guide and Python implementation for the 'Binary Search' problem.
Problem Statement
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, return its index. Otherwise, return -1.
You must write an algorithm with O(log n) runtime complexity.
Write a function search(nums: List[int], target: int) -> int.
- •1 <= len(nums) <= 10^4
- •-10^4 < nums[i], target < 10^4
- •All integers in nums are unique
- •nums is sorted in ascending order
Examples
nums = [-1, 0, 3, 5, 9, 12], target = 9
4
9 exists in nums and its index is 4.
nums = [-1, 0, 3, 5, 9, 12], target = 2
-1
2 does not exist in nums so return -1.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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