Study 5 —— 流程控制

if 條件：
　　知足條件後要執行的代碼
else:
　　if條件不知足就執行這裏

#_*_coding:utf-8_*_
---------------------------------------------------	
#單分支
username = 'Lisa'
password = '123'
Username = input('Input your name: ')
Password = input('Input your password: ')

if Username == username and Password == password :
　　print('Welcome to the system!')
else :
　　print('The username or password is not right!')
---------------------------------------------------
#雙分支
Name = input('Input your name: ')
Sex = input('Input your sex: ')
Age = int(input('Input your age: '))

if Sex == 'girl' :
　　if Age < 18 :
　　　　print('She is a little princess!')
　　else :
　　　　print('She is going to marry!')
else :
　　print('No one likes him!')
---------------------------------------------------
#多分支
(1)
age = 26

user_guess = int(input('Input a number you guess: '))

if user_guess == age :
　　print('You are right!')
elif user_guess > age :
　　print('Try smaller!')
else :
　　print('Try bigger!')

(2)#根據成績不一樣，給予不一樣等級
Score = int(input('Input Score: '))

if Score <= 100 :
　　if Score >= 90 : 
　　　　print('A')
　　elif Score >= 80 :
　　　　print('B')
　　elif Score >= 60 :
　　　　print('C')
　　elif Score >= 40 :
　　　　print('D')
　　elif Score >= 0 :
　　　　print('E')
　　else :
　　　　print('You are a fool!')
else :
　　print('Must be less than 100!')