# Author:zyl
_username = 'zyl'
_password = 'zyl123'
username = input("username:")
password = input("password:")
print(username, password)
if _username == username and _password == password:
print("welcome user {name} login...".format(name=username))
else:
print("invalid usernaem or password!")
# indentationError表示缩进错误
# if和else后都必须加冒号“:”
age_of_oldboy = 56
guess_age = int(input("guess age:")) # 强制转换数据类型
if guess_age == age_of_oldboy:
print("yes,you got it.")
elif guess_age > age_of_oldboy:
print("think smaller...")
else:
print("think bigger!")