save project

diy2.py

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