generate_huffman_tree(SymbolsAndWeights, HuffmanTree) :-
initialize_tree(SymbolsAndWeights, SymbolsAndWeightsTree),
generate_huffman_tree_aux(SymbolsAndWeightsTree, HuffmanTree).

generate_huffman_tree_aux(SymbolsAndWeightsTree, HuffmanTree) :-
insert_sort(SymbolsAndWeightsTree, Ordered),
generate_tree(Ordered, HuffmanTree).


initialize_tree([[Symbol, Weight]|SymbolsAndWeights], SymbolsAndWeightsTree) :-
initialize_tree(SymbolsAndWeights, Temp),
append([t([[Symbol], Weight], nil, nil)], Temp, SymbolsAndWeightsTree).
initialize_tree([],[]).

%generate_tree/2: huffman algorithm for tree generation.
generate_tree([A,B|Ordered], Tree) :-
unite(A, B, United),
append([United], Ordered, OrderedFinal),
generate_huffman_tree_aux(OrderedFinal, Tree),
!.
generate_tree([A|[]], A) :- !.

Assinado pelo pie

Obrigado por ser esse meu amigo espetacular. <3
Te amo muito

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