diff --git a/notes/38. 字符串的排列.md b/notes/38. 字符串的排列.md
index 149b3772..f432358d 100644
--- a/notes/38. 字符串的排列.md	
+++ b/notes/38. 字符串的排列.md	
@@ -15,7 +15,6 @@ public ArrayList<String> Permutation(String str) {
     if (str.length() == 0)
         return ret;
     char[] chars = str.toCharArray();
-    Arrays.sort(chars);
     backtracking(chars, new boolean[chars.length], new StringBuilder());
     return ret;
 }