#猜年龄大小,用户最多猜三次
age = 50
i = 0
while i < 3:
    guess_age = int(input("Please input your answer:"))
    if guess_age > age:
        print("too big...try again please")
    elif guess_age < age:
        print("too small...try again please")
    else:
        print("You guessed it!")
        break
    i += 1
    if i == 3:
#猜年龄,每隔三次询问是否继续玩
age = 50
for i in range(1,100):
    guess_age = int(input("Please input your answer:"))
    if guess_age > age:
        print("too big...try again please")
    elif guess_age < age:
        print("too small...try again please")
    else:
        print("You guessed it !")
    if i%3 == 0:
        choice = input("Would you like play again? yes or no")
        if choice == "yes":
            continue
        if choice == "no":
            break
    else:
        continue#登录验证,输入错误三次锁定用户
f = open(‘c:/user_passwd.txt‘,‘r‘)
j = 3
system_user_name = str(f.readline())
system_passwd = str(f.readline())
f.close()
for i in range(1,5):
    user_name = str(input("Please input your UserID:"))
    password = str(input("passwd:"))
    if i == 3:
        s = open(‘c:/user_passwd.txt‘, ‘r+‘)
        s.write("\nlocked")
        s.close()
        print("This user is locked!")
        break
    else:
        if user_name + ‘\n‘ == system_user_name and password == system_passwd:
            print("Welcome" + user_name + ‘\n‘ + "Have a good time!")
            break
        else:
            j -= 1
            i += 1            print("UserID or password is wrong,Please try once again and you have " + \              str(j) + ‘times choice‘)原文地址:http://altboy.blog.51cto.com/5440160/1911078