save project

diy2.py

 username = "python"
 userpassword = "123456"
+i=3
 while True:
+    if i>0:
         name = input("请输入用户名:")
         password = input("请输入密码:")
+        i-=1
         if name == username and password == userpassword:
-        break
             print("登录成功!")
+            break
         print("用户名和密码错误!请重新输入")
-print("欢迎来到贝尔编程!")
-if name!=username:
+        if name!=username:
+            continue
         print("请重新输入名字")
-if password!=userpassword:
+        if password!=userpassword:
+            continue
+    else:
+        if i<=0:
+            exit()
     print("请重新输入密码")
+print("欢迎来到贝尔编程!")