python入门-WHILE循环，python入门-while,1 使用while循

python入门-WHILE循环，python入门-while,1 使用while循

1 使用while循环

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

2 让用户选择退出

prompt = "tell me somthing, and i will repeat it back to you"prompt = "\nEnter ‘quit‘ to end the program"message = ""while message != ‘quit‘:    message=input(prompt)    if message!=‘quit‘:        print(message)

3 使用标志

prompt = "tell me somthing, and i will repeat it back to you"prompt = "\nEnter ‘quit‘ to end the program"active = Truewhile active:    message = input(prompt)    if message == ‘quit‘:        active = False    else:        print(message)

4 使用break退出循环

prompt = "\nPlease enter the name of a city you have visited:"prompt += "\n(enter ‘quit‘ when you are finished.)"while True:    city = input(prompt)    if city == ‘quit‘:        break    else:        print("I‘d love to go to" + city.title() + "!")

5 在循环中使用continue

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

6 使用while循环来处理列表和字典

unconfirmed_users = [‘alice‘,‘brian‘,‘candace‘]confirmed_users = []while unconfirmed_users:    current_user = unconfirmed_users.pop()    print("verifying user:" + current_user.title())    confirmed_users.append(current_user)print("\n the following users have been confirmed:")for confirmed_user in confirmed_users:    print(confirmed_user.title())

7 删除特定的列表元素

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

8使用用户输入来填充字典

responses = {}polling_active = Truewhile polling_active:    name = input("\n what is your name?")    response = input("which mountain would you like to climb someday")    responses[name] = response    repeat = input("would you like to let another person respond?(yes or no")    if repeat == ‘no‘:        polling_active = Falseprint("\n --poll results--")for name,response in responses.items():    print(name + "would like to climb" + response + ".")

python入门-WHILE循环