diff --git a/problems/0704.二分查找.md b/problems/0704.二分查找.md
index 7160a884..3a44bb57 100644
--- a/problems/0704.二分查找.md
+++ b/problems/0704.二分查找.md
@@ -225,14 +225,13 @@ class Solution:
     def search(self, nums: List[int], target: int) -> int:
         if nums is None or len(nums)==0:
             return -1
-        l=0
-        r=len(nums)-1
-        while (l<=r):
-            m = round(l+(r-l)/2)
+        l,r=0,len(nums)
+        while (l<r):
+            m = round(l+(r-l)//2)
             if nums[m] == target:
                 return m     
             elif nums[m] > target:
-                r=m-1
+                r=m
             else:
                 l=m+1
         return -1