记录python新掌握的知识点---持续更新

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2018-10-16更新

3、判断输入的字符串是否为正整数

prompt = "\n请输入年龄:"
prompt +="\n输入'quit'退出程序."
message = ''

while message != 'quit':
    message = input(prompt)
    if message.isdigit():
        age = int(message)
        if age < 3:
            print('岁数%s,观众免费' % (message))
        elif age < 13:
            print('岁数%s,票价为10$' % (message))
        else:
            print('岁数%s,票价为15$' % (message))
    elif message == 'quit':
        break
    else:
        print("请输入正确的年龄(正整数).")

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2、字典嵌套

citys = {
    'beijing':{
        'country':'china',
        'population':'21,710,000',
        'fact':'the capital of China',
    },
    'wahsington':{
        'country':'american',
        'population':'694,000',
        'fact':'the capital of US'
    },
    'paris':{
        'country':'france',
        'population':'2,244,000',
        'fact':'the capital of France'
    },
}

citys['london'] = {
    'country': 'britain',
    'population': '8,136,000',
    'fact': 'the capital of France'
}

for city,city_info in citys.items():
    print('\nCity:' + city.title())
    print('\tcountry:' + city_info['country'].title())
    print('\tpopulation:' + city_info['population'])
    print('\tfact:' + city_info['fact'])

运行结果如下：

City:Paris
country:France
population:2,244,000
fact:the capital of France


City:Beijing
country:China
population:21,710,000
fact:the capital of China


City:Wahsington
country:American
population:694,000
fact:the capital of US


City:London
country:Britain
population:8,136,000
fact:the capital of France

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1、打印时引用参数

river = {
    'changjiang':'china',
    'nile':'egypt',
    'amazonas':'brazil'
    }

for k,v in river.items():
    print("The %s runs through %s." % (k.title(),v.title()))

运行结果如下：

The Amazonas runs through Brazil.
The Nile runs through Egypt.
The Changjiang runs through China.