save project

diy2.py

+username = "python"
+userpassword = "123456"
+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!")
+    print("用户名和密码错误!请重新输入")
+print("欢迎来到贝尔编程!")
\ No newline at end of file

diy3.py

+username = "python"
+userpassword = "123456"
+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
+    print("输入错误，请重新输入。")
+print("欢迎来到贝尔编程！")
\ No newline at end of file

diy4.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:
+            print("登录成功!")
+            break
+        if name != username:
+            input("请重新输入用户名:")
+            print("你还有"+str(i)+"次机会")
+            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 password != userpassword:
+            input("请重新输入密码:")
+            print("你还有"+str(i)+"次机会")
+    else:
+        print("你的账户已被锁定，请带着身份证到我司解锁！")
+        exit()
+print("欢迎来到贝尔编程！")
\ No newline at end of file