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pythonlistnestedalphabeticalsorting

Python - Order nested list in alphabetical way

I have the following list:

["stephane", "philippe", "hélène", ["hugo", "jean-michel", "fernand"], "gustave"]

And I would like to order it like this:

["gustave", "hélène", ["fernand", "hugo", "jean-michel"], "philippe", "stephane"]

NB: If there is a nested list following a user, this list must stay to the right of this user.

In addition to that all nested lists works the same way. It's recursive.

Solution

  • I've used Ned's proposal and came up with this:

    d = {
    "stephane": {}, 
    "philippe": {}, 
    "helene": {
        "hugo": {}, 
        "jean-michel": {},
        "fernand": {},
    }, 
    "gustave": {},
}

def sort_dict_as_list(d):
    sorted_list = []
    for k, v in sorted(d.items()):
        if k:    
            sorted_list.append(k)
        if v:
            sorted_list.append(v)
    return sorted_list

def sort_recursive(d):
    if d:
        for k, v in d.items():
            d[k] = sort_recursive(v)
        return sort_dict_as_list(d)
    else:
        return d

if __name__ == "__main__":
    print sort_recursive(d)

    Output

    python sortit.py
['gustave', 'helene', ['fernand', 'hugo', 'jean-michel'], 'philippe', 'stephane']

    I haven't tested it thoroughly, but it's a starting point. I was trying to solve it with a list as a data structure, but I ended up nesting recursive functions and it was way too ugly... Ned's proposal was really good.