diff --git a/problems/0151.翻转字符串里的单词.md b/problems/0151.翻转字符串里的单词.md
index a12d8f76..dc12ae23 100644
--- a/problems/0151.翻转字符串里的单词.md
+++ b/problems/0151.翻转字符串里的单词.md
@@ -442,7 +442,7 @@ class Solution:
             while left <= right and s[left] == ' ':    #去除开头的空格
                 left += 1
             while left <= right and s[right] == ' ':   #去除结尾的空格
-                right = right-1
+                right -= 1
             tmp = []
             while left <= right:                      #去除单词中间多余的空格
                 if s[left] != ' ':