账户登录

__author: Administrator
date: 2018/6/18

_user = "fangyuan"
_passwd = "abc123"

for i in range(3):
    username = input("username:")
    password = input("password:")

    if username == _user and password == _passwd:
        print("welcome %s login...." % _user)
        break#跳出，中断
    else:
        print("invalid username or password")
else:
    print("大哥你是猪么。")

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_user = "fangyuan"
_passwd = "abc123"

passed_abc = False #假，不成立

for i in range(3):
    username = input("username:")
    password = input("password:")
    if username == _user and password == _passwd:
        print("welcome %s login..." % _user)
        passed_abc = True #真，成立
        break
    else:
        print("invalid username and password...")
if not passed_abc:
    print("你是猪么。。。")

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_user = "fangyuan"
_passwd = "abc123"

counter = 0
while counter < 3:
    username = input("username:")
    password = input("password:")
    if username == _user and password == _passwd:
        print("welcome %s login..." % _user)
        break
    else:
        print("invalid username and password...")
        counter += 1
    if counter == 3:
        keep_going = input("你还想继续吗，y/n:")
        if keep_going == "y":
            counter = 0
else:
    print("你是猪么。。。")
 ___________________________________________
abc = False
for i in range(10):
    print(i)
    for j in range(10):
        print("diss",j)
        if j == 6:
            abc = True
            break
    if abc:
        break