根据字典替换列表中值的 Pythonic 方法

Question

我需要根据 Python 字典中包含的值转换列表值。

我有一个如下列表:

lst = ["hello", "word", "bye", "my", "friend", "hello"]

还有一个使用集群过程获得的字典，所以键是标签，值是类别:

my_dict = {0: ["hello", "word"], 1: ["my", "friend"], 2: ["bye"]}

我需要更快地将原始列表转换为:

new_lst = [0, 0, 2, 1, 1, 0]

考虑在实际情况下，列表长度接近 60k，因此我需要一种有效的方法来执行此操作。

Answer 1

lst = ["hello", "word", "bye", "my", "friend", "hello"]
my_dict = {0: ["hello", "word"], 1: ["my", "friend"], 2: ["bye"]}

inverse_dict = {b:a for a,c in my_dict.items() for b in c}

new_lst = [inverse_dict.get(a) for a in lst]