diff --git a/semester3/pset4/7-3-航空公司VIP客户查询.c b/semester3/pset4/7-3-航空公司VIP客户查询.c
index 633a72a..47b2eaa 100644
--- a/semester3/pset4/7-3-航空公司VIP客户查询.c
+++ b/semester3/pset4/7-3-航空公司VIP客户查询.c
@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+// when size is too small, the table will overflow.
 #define SIZE 100023
 #define IDLEN 19
 #define P 13