save dictionary to a file without brackets.

Andrew Cooper amc96 at cam.ac.uk
Thu Aug 9 18:03:26 EDT 2012


On 09/08/2012 22:34, Roman Vashkevich wrote:
> Actually, they are different.
> Put a dict.{iter}items() in an O(k^N) algorithm and make it a hundred thousand entries, and you will feel the difference.
> Dict uses hashing to get a value from the dict and this is why it's O(1).
> 

Sligtly off topic, but looking up a value in a dictionary is actually
O(n) for all other entries in the dict which suffer a hash collision
with the searched entry.

True, a sensible choice of hash function will reduce n to 1 in common
cases, but it becomes an important consideration for larger datasets.

~Andrew



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