diy2.py

i=0
username = "QWERTYUIOPASDFGHJKLZXCVBNM"
userpassword = "MNBVCXZLKJHGFDSAPOIUYTREWQ"
while True:
    if i<3:
        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:
            print("用户名错误!请重新输入")
        continue
        if password != userpassword:
            print("密码错误!请重新输入")  
        if password != userpassword and name != username:
            print("用户名和密码错误!请重新输入")
    else:
        print("!@#$%^&*()_+|}{:?><")
        exit()
print("欢迎来到贝尔编程!")