求助：如何用mathematica写霍夫曼编码(Huffman)的程序

ShannonCode[SC_]:=
Module[{SCP,n,pa,i,max,er,B},
SCP=Sort[Transpose[SC],#1[[2]]>=#2[[2]]&](*排序*);
n=Length[SCP];
pa=0;
AppendTo[SCP[[1]],pa];
Table[AppendTo[SCP[[i]],SCP[[i-1,2]]+SCP[[i-1,3]]],{i,2,Length[SCP]}];
Table[AppendTo[SCP[[i]],-Log[2,SCP[[i,2]]]],{i,1,Length[SCP]}];Table[AppendTo[SCP[[i]],Ceiling[SCP[[i,4]]]],{i,1,Length[SCP]}];max=Last[SCP][[5]];
Table[er=RealDigits[SCP[[i,3]],2,2*max,-1];AppendTo[SCP[[i]],TableForm[er[[1]][[1;;SCP[[i,5]]]],TableDirections->Row,TableSpacing->{0.1,2.5}]],{i,1,Length[SCP]}];
B=TableForm[SCP,TableHeadings->{None,{"Subscript[x, i]","p(Subscript[x, i])","Subscript[p, a](Subscript[x, j])","-logp(Subscript[x, i])","Subscript[k, i]","码字"}},TableSpacing->{1.0,2.5},TableAlignments->Left];
Return;
];
SC={X,PX}={{Subscript[x, 1],Subscript[x, 2],Subscript[x, 3],Subscript[x, 4],Subscript[x, 5],Subscript[x, 6]},{0.25,0.25,0.20,0.15,0.10,0.05}};
ShannonCode[SC]

看来两眼维基百科，写了这个，不知对不对。。。
split[probs_] /; Length[probs] == 1 := probs;split[probs_] /; Length[probs] == 2 := List /@ probs;split[probs_] := Block[{len = Length[probs], ac = Accumulate[probs], tol = Total[probs], index}, index = SortBy[Range[1, len - 1], Abs[tol/2 - ac[[#]]] &][[1]]; {split[Take[probs, index]], split[Drop[probs, index]]}];HannonCode[x_, px_] := Block[ {sorted, sortedpx, h}, sorted = Reverse[SortBy[Transpose[{x, px}], Last]]; sortedpx = sorted[[All, 2]]; Grid[{sorted[[All, 1]], List @@@ Flatten[MapIndexed[h @@ Most[(#2 - 1)] &, split[sortedpx], {-1}]]}, Frame -> All] ]

Huffman编码：

ClearAll[huffman];huffman[data_] := Module[{huff, code}, huff[list_] /; Length@list == 1 := list; huff[{{a_, b_}, {c_, d_}, tail___}] := huff[SortBy[{{{a, c}, b + d}, tail}, Last]]; List @@@ Flatten[MapIndexed[code[#1, #2 - 1] &, huff[data][[1, 1]], {-1}]]];

兄弟，去看看Power Mathematica Programming with Mathematica: The Kernal，原封不动的哈夫曼编码和解码例子，代码还比较优化。

写好了请帮忙贴在这里： http://rosettacode.org/wiki/Huffman_coding