auto save

diy2.py

 username = "python"
 userpassword = "123456"
+i = 3
 while True:
-    name = input("请输入用户名:")
-    password = input("请输入密码:")
-    if name == username:
-        if password == userpassword:
-            print("登录成功！")
-            print("欢迎来到贝尔编程!")
-            break
-        print("密码错误！")
-    print("用户名错误！")
+    if i>0:
+        name = input("请输入用户名:")
+        password = input("请输入密码:")
+        i-=1
+        if name == username:
+            if password == userpassword:
+                print("登录成功！")
+                print("欢迎来到贝尔编程!")
+                exit()
+            print("密码错误！")
+        print("用户名错误！")