From fde9817fba095b5c0f8a4b512c0d8f8025ae42e5 Mon Sep 17 00:00:00 2001
From: Wenru Dong <dongwenru.aaron.shenyang@gmail.com>
Date: Thu, 25 Oct 2018 20:41:01 +0100
Subject: [PATCH] Binary search in python

---
 python/15_bsearch/bsearch.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 python/15_bsearch/bsearch.py

diff --git a/python/15_bsearch/bsearch.py b/python/15_bsearch/bsearch.py
new file mode 100644
index 00000000..dc091b29
--- /dev/null
+++ b/python/15_bsearch/bsearch.py
@@ -0,0 +1,22 @@
+"""
+    Author: Wenru
+"""
+
+from typing import List
+
+def bsearch(nums: List[int], target: int) -> int:
+    """Binary search of a target in a sorted array
+    without duplicates. If such a target does not exist,
+    return -1, othewise, return its index.
+    """
+    low, high = 0, len(nums) - 1
+    while low <= high:
+        mid = low + (high - low) // 2
+        if nums[mid] == target:
+            return mid
+        elif nums[mid] < target:
+            low = mid + 1
+        else:
+            high = mid - 1
+    
+    return -1