Merge pull request wangzheng0822#259 from dreamkong/master

二分查找递归实现 Python

Author: wangzheng0822

python/15_bsearch/bsearch_recursion.py

@@ -0,0 +1,22 @@
+"""
+ Author: dreamkong
+"""
+
+from typing import List
+
+
+def bsearch(nums: List[int], target: int) -> int:
+ return bsearch_internally(nums, 0, len(nums)-1, target)
+
+
+def bsearch_internally(nums: List[int], low: int, high: int, target: int) -> int:
+ if low > high:
+ return -1
+
+ mid = low+int((high-low) >> 2)
+ if nums[mid] == target:
+ return mid
+ elif nums[mid] < target:
+ return bsearch_internally(nums, mid+1, high, target)
+ else:
+ return bsearch_internally(nums, low, mid-1, target)