python基础（六）

#函数input()，程序暂停运行，等待用户输入一些文本，获取输入后，将其存储在一个变量中
message = input("tell me")
print(message)

tell mehi
hi

name = input("Please enter your name:")
print("Hello, " + name + "!")

Please enter your name:cui
Hello, cui!

prompt = "hihi"
prompt = "
what is your name"

name = input(prompt)
print("
Hello, " + name + "!")

what is your namecui

Hello, cui!

#使用int()来获取数值输入，将用户输入解读为字符串,无法与数值进行比较
age = input("How old are you?")

How old are you?22

age

'22'

age >= 18

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-6-4ce6028355cc> in <module>
----> 1 age >= 18

TypeError: '>=' not supported between instances of 'str' and 'int'

age = int(age)

age >= 18

True

height = input("How tall are you, in inches")
height = int(height)

How tall are you, in inches71

if height >= 36:
    print("
You are tall enough to ride!")
else:
    print("
You'll be able to ride")

 

You are tall enough to ride!

#求模运算符
4%3

#用于判断奇数偶数
number = input("enter a number, and I'll tell you if it's even or odd:")
number = int(number)

if number % 2 == 0:
    print("
The number " + str(number) + "is even.")
else:
    print("
The number " + str(number) + "is odd.")

prompt = "
Tell me something, and I will repeat it back to you:"
prompt += "
Enter 'quit' to end the program."

message = ""
while message != 'quit':
    message = input(prompt)
    
    if message != 'quit':
        print(message)

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.hihi
hihi

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.露露
露露

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.xixi
xixi

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.quit

#用于判断奇数偶数
number = input("enter a number, and I'll tell you if it's even or odd:")
number = int(number)

if number % 2 == 0:
    print("
The number " + str(number) + "is even.")
else:
    print("
The number " + str(number) + "is odd.")

enter a number, and I'll tell you if it's even or odd:51

The number 51is odd.

#while循环
current_number = 1
while current_number <= 5:
    print(current_number)
    current_number += 1

1
2
3
4
5

prompt = "
Tell me something, and I will repeat it back to you:"
prompt += "
Enter 'quit' to end the program."
message = ""
while message != 'quit':
    message = input(prompt)
    print(message)

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.hi
hi

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.hello
hello

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.quit
quit

prompt = "
Tell me something, and I will repeat it back to you:"
prompt += "
Enter 'quit' to end the program."
message = ""
while message != 'quit':
    message = input(prompt)
    
if message != 'quit':
    print(message)

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.hi

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.hello

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.quit

#使用标志
prompt = "
Tell me something, and I will repeat it back to you:"
prompt += "
Enter 'quit' to end the program."

active = True
while active:
    message = input(prompt)
    
    if message == 'quit':
        active = False
    else:
        print(message)

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.hi
hi

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.hello
hello

Tell me something, and I will repeat it back to you:
Enter 'quit' to end the program.quit

#使用break退出循环
prompt = "
Please enter the name of a city you have visited."
prompt += "
(enter 'quit' when you are finished.)"

while True:
    city = input(prompt)
    
    if city == 'quit':
        break
    else:
        print("mmmmmm" + city.title() + "!")

Please enter the name of a city you have visited.
(enter 'quit' when you are finished.)nanjing
mmmmmmNanjing!

Please enter the name of a city you have visited.
(enter 'quit' when you are finished.)guangdong
mmmmmmGuangdong!

Please enter the name of a city you have visited.
(enter 'quit' when you are finished.)quit

Please enter the name of a city you have visited.
(enter 'quit' when you are finished.)nanjing
mmmmmmNanjing!

Please enter the name of a city you have visited.
(enter 'quit' when you are finished.)guangdong
mmmmmmGuangdong!

Please enter the name of a city you have visited.
(enter 'quit' when you are finished.)quit

#continue
number = 0
while number < 10:
    number += 1
    if number % 2 == 0:
        continue
    print(number)

1
3
5
7
9

#避免无限循环
#处理列表和字典
unconfirmed_users = ['baba','mama','jing']
confirmed_users = []

while unconfirmed_users:
    current_user = unconfirmed_users.pop()
    print("vertify:" + current_user.title())
    confirmed_users.append(current_user)

vertify:Jing
vertify:Mama
vertify:Baba

print("new:")
for confirmed_user in confirmed_users:
    print(confirmed_user.title())

new:
Jing
Mama
Baba

#删除特定值的所有列表元素
pet = ['dog','cat','dog','goldfish','cat','rabbit','cat']
print(pet)

['dog', 'cat', 'dog', 'goldfish', 'cat', 'rabbit', 'cat']

pets = ['dog','cat','dog','goldfish','cat','rabbit','cat']
while 'cat' in pets:
    pets.remove('cat')
    
print(pets)

['dog', 'dog', 'goldfish', 'rabbit']

#使用用户输入来填充字典
responses = {}

#设置一个标志，指出调查是否继续
polling_active = True
while polling_active:
    #提示输入被调查者的名字和回答
    name = input("
What is your name?")
    response = input("Which mountain would you like to climb someday?")
    
    #将答卷存储在字典中
    responses[name] = response
    
    #看看是否还有人要参与调查
    repeat = input("Would you like to let another person respond?(yes/no)")
    if repeat == 'no':
        polling_active = False

What is your name?cui
Which mountain would you like to climb someday?huang
Would you like to let another person respond?(yes/no)yes

What is your name?lu
Which mountain would you like to climb someday?zijin
Would you like to let another person respond?(yes/no)yes

What is your name?ting
Which mountain would you like to climb someday?tai
Would you like to let another person respond?(yes/no)no

 #调查结束，显示结果
print("
--- Poll Results ---")
for name,response in responses.items():
    print(name + " would like to climb " + response + ".")

--- Poll Results ---
cui would like to climb huang.
lu would like to climb zijin.
ting would like to climb tai.