auto save

diy2.py

@@ -5,5 +5,10 @@ while True:
     password = input("请输入密码:")
     if name == username and password == userpassword:
         print("登录成功!")
-    print("用户名和密码错误!请重新输入")
+        break
+    if name != username:
+        print("用户名不存在,请重新输入!")
+        continue
+    if password != userpassword:
+        print("密码输入有误,请重新输入!")
 print("欢迎来到贝尔编程!")
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