給定一個以字符串列表作為其值的字典，您將如何檢索列表包含所有其他列表唯一的字符串的所有鍵？

Question

例如，如果字典是這樣的：

myDict = {"egg sandwich":["bread", "lettuce", "mayo","egg"], 
          "sad sandwich":["bread","lettuce","mayo"],
          "ham sandwich":["bread","lettuce","mayo","ham"],
          "healthy sandwich":["lettuce"],
          "breakfast sandwich":["bread","egg","mayo"]}

該函數應返回“火腿三明治”，因為它是唯一包含與所有其他列表進行比較時所獨有的成分（火腿）的三明治。

Answer 1

這似乎有效：

def get_unique_item(d):
    all_ingredients = [y for x in d.values() for y in x]

    output = []
    for name, ingredients in d.items():
        for ingredient in ingredients:
            if all_ingredients.count(ingredient) == 1:
                output.append(name)
                break

    return output

myDict = {"egg sandwich":["bread", "lettuce", "mayo","egg"], 
          "sad sandwich":["bread","lettuce","mayo"],
          "ham sandwich":["bread","lettuce","mayo","ham"],
          "healthy sandwich":["lettuce"],
          "breakfast sandwich":["bread","egg","mayo"]}


print(get_unique_item(myDict))

輸出：

['ham sandwich']

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基本上，我們創建一個所有成分的所有出現的列表，對於每個三明治，我們檢查是否有任何成分只出現一次。

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如果你真的想，你可以把它變成一個單行列表理解：

[name for name, ingredients in d.items() if any([y for x in d.values() for y in set(x)].count(i) == 1 for i in ingredients)]