revisited: enumerate is more efficient than list.index clear solution for Sort Array by Element Frequency by juestr - python coding challenges

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revisited: enumerate is more efficient than list.index solution in Clear category for Sort Array by Element Frequency by juestr

from collections import Counter

def frequency_sort(items):
    counts = Counter(items)
    order = { k: i for i, k in enumerate(counts) }
    return sorted(items, key=lambda x: (-counts[x], order[x]))

May 12, 2019

Comments:

rherron on May 27, 2019, 11:40 p.m.
Interesting. I didn't realize insertion order was captured in dictionaries, so it took me a minute to figure out why enumerate was consistently producing a list in the correct order. Similar to my solution, but I used list.index instead of enumerate as the secondary key in sorted.

H0r4c3 on April 29, 2023, 9:39 p.m.
Great solution! Lesson learned, enumerate for the win.

List, list and list again

0 %

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