save project

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 and password == userpassword:
-        print("登录成功！！")
-        break
-    if username != name:
-        print("用户名错误！")
-    elif password != userpassword:
-        print("密码错误！")
+    if i>0:
+        name = input("请输入用户名:")
+        password = input("请输入密码:")
+        if name == username and password == userpassword:
+            print("登录成功！！")
+            break
+        if username != name:
+            print("用户名错误！")
+            i -= 1
+            print("您还有",i,"次输入机会")
+        elif password != userpassword:
+            print("密码错误！")
+            i -= 1
+            print("您还有",i,"次输入机会")
+    else:
+        print("登录次数受限")
+        exit()
 print("欢迎来到贝尔编程!")