Summary

1. 二分搜索模板

1.1 基本的二分搜索算法

1. 手工实现

   class Solution:
       def search(self, nums: List[int], target: int) -> int:
           if not nums:
               return -1
           l, r = 0, len(nums) - 1
           while l <= r:
               mid = l + (r - l) // 2
               if nums[mid] < target:
                   l = mid + 1
               elif nums[mid] > target:
                   r = mid - 1
               else:
                   return mid
   
           return -1
   

2. 使用 Python bisect 库

       def search_2(self, nums: List[int], target: int) -> int:
           res = bisect.bisect_left(nums, target)
           if res != len(nums) and nums[res] == target:
               return res
           return -1