29 lines
866 B
Python
29 lines
866 B
Python
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price = {
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"ACME": 45.23,
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"AAPL": 612.78,
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"IBM": 205.55,
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"HPQ": 37.2,
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"FB": 10.75
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}
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# 对这样的数据,有时候我们想找到最大值对应的键
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# 传统方法长这样
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a = max(price.values())
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print(a)
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for key, value in price.items():
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if value == a:
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print(key)
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# 显然,我们要对字典里的这些东西进行遍历才能根据值把键找出来
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# 如果我们不想要这样的开销,可以把键值反转:
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max_price = max(zip(price.values(), price.keys()))
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print(max_price)
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# 注意,在对键值反转的zip中使用max和min这类函数时需要注意,如果出现:
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# a = {10, "AA"}, b = {10, "ZZ"}的情况
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# 由于值相同,会根据键大小返回结果
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# 所以如果有多个值相同的字段,还得是老办法
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max_price = [key for value, key in zip(price.values(), price.keys()) if value == a]
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print(max_price)
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