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Just another update

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Ingy döt Net 2015-02-20 00:35:01 -05:00
parent a25938f123
commit 00a190b0a6
6591 changed files with 94363 additions and 23227 deletions
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13
Task/Huffman-coding/Mathematica/huffman-coding.math Normal file
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huffman[s_String] := huffman[Characters[s]];
huffman[l_List] := Module[{merge, structure, rules},
(*merge front two branches. list is assumed to be sorted*)
merge[k_] := Replace[k, {{a_, aC_}, {b_, bC_}, rest___} :> {{{a, b}, aC + bC}, rest}];
structure = FixedPoint[
Composition[merge, SortBy[#, Last] &],
Tally[l]][[1, 1]];
rules = (# -> Flatten[Position[structure, #] - 1]) & /@ DeleteDuplicates[l];
{Flatten[l /. rules], rules}];