Distribution-Sensitive Construction of Minimum-Redundancy Prefix Codes
نویسندگان
چکیده
A new method for constructing minimum-redundancy prefix codes is described. This method does not build a Huffman tree; instead it uses a property of optimal codes to find the codeword length of each weight. The running time of the algorithm is shown to be O(nk), where n is the number of weights and k is the number of different codeword lengths. When the given sequence of weights is already sorted, it is shown that the codes can be constructed using O(log n) comparisons, which is sub-linear if the value of k is small.
منابع مشابه
Optimal Prefix Codes with Fewer Distinct Codeword Lengths are Faster to Construct
A new method for constructing minimum-redundancy prefix codes is described. This method does not explicitly build a Huffman tree; instead it uses a property of optimal codes to find the codeword length of each weight. The running time of the algorithm is shown to be O(nk), which is asymptotically faster than Huffman’s algorithm when k = o(log n), where n is the number of weights and k is the nu...
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