if语句

user='liangml'
passwd='liangml'
username=input('username:')
password=input('password:')
#优化前
'''
if user ==  username:
print('usernameiscorrect...')
if passwd == password:
print('welcomelogin...')
else:
print('passwordifinvalid...')
else:
print('user name is not...')
'''
'''
#优化后
if user == username and passwd == password:
print('Welcomelogin')
else:
print('Invalid user name or password...')
'''

--------------------分界线----------------------
If语句猜年龄小游戏
age=22
guess_num=int(input('inputyourguessnum:'))
if  guess_num==age:
print('Congratulations!yougotit.')
elif    guess_num>age:
print('Thinksmaller!')
else:
print('ThinkBig...')