Phi*_*ham 7 python iteration recursion dictionary list
假设我有一个如下列表:
mylist = ['a','b','c','d']
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是否可以从此列表中创建以下dict 而不使用递归/递归函数?
{
'a': {
'b': {
'c': {
'd': { }
}
}
}
}
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Mar*_*ers 11
对于简单的情况,只需从结束或开始迭代和构建:
result = {}
for name in reversed(mylist):
result = {name: result}
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要么
result = current = {}
for name in mylist:
current[name] = {}
current = current[name]
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第一种解决方案也可以表示为单线,使用reduce():
reduce(lambda res, name: {name: res}, reversed(mylist), {})
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至少对于这个简单的情况,是的:
my_list = ['a', 'b', 'c', 'd']
cursor = built_dict = {}
for value in my_list:
cursor[value] = {}
cursor = cursor[value]
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