diff --git a/【实践课内】13.指针1/6-4 移动字母.c b/【实践课内】13.指针1/6-4 移动字母.c
index 5ee7705..c859ee2 100644
--- a/【实践课内】13.指针1/6-4 移动字母.c	
+++ b/【实践课内】13.指针1/6-4 移动字母.c	
@@ -1,5 +1,6 @@
 void Shift(char s[]) {
     int s_len = strlen(s);
     memcpy(s + s_len, s, 3);
-    memcpy(s + 3, s, s_len);
+    memcpy(s, s + 3, s_len);
+    s[s_len] = '\0';
 }