From 3827dfeeedc3baac5b8ad6df9fe6b1595df9505e Mon Sep 17 00:00:00 2001
From: dengshilong <dengshilong1988@gmail.com>
Date: Tue, 14 May 2019 19:20:47 +0800
Subject: [PATCH] =?UTF-8?q?fix:=20=E4=BF=AE=E5=A4=8D=E4=BA=8C=E5=88=86?=
 =?UTF-8?q?=E6=9F=A5=E6=89=BE=E7=AE=97=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .gitignore |  1 +
 Readme.md  | 18 +++++++++---------
 2 files changed, 10 insertions(+), 9 deletions(-)
 create mode 100644 .gitignore

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..485dee6
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.idea
diff --git a/Readme.md b/Readme.md
index 12721ad..5d71338 100644
--- a/Readme.md
+++ b/Readme.md
@@ -1569,21 +1569,21 @@ def node(l1, l2):
 ```python
 
 #coding:utf-8
-def binary_search(list,item):
+def binary_search(list, item):
     low = 0
-    high = len(list)-1
-    while low<=high:
-        mid = (low+high)/2
+    high = len(list) - 1
+    while low <= high:
+        mid = (high - low) / 2 + low    # 避免(high + low) / 2溢出
         guess = list[mid]
-        if guess>item:
-            high = mid-1
-        elif guess<item:
-            low = mid+1
+        if guess > item:
+            high = mid - 1
+        elif guess < item:
+            low = mid + 1
         else:
             return mid
     return None
 mylist = [1,3,5,7,9]
-print binary_search(mylist,3)
+print binary_search(mylist, 3)
 
 ```