A Space-Saving Linear-Time Algorithm for Grammar-Based Compression
نویسندگان
چکیده
A space-efficient linear-time approximation algorithm for the grammar-based compression problem, which requests for a given string to find a smallest context-free grammar deriving the string, is presented. The algorithm consumes only O(g∗ log g∗) space and achieves the worstcase approximation ratio O(log g∗ log n), with the size n of an input and the optimum grammar size g∗. Experimental results for typical benchmarks demonstrate that our algorithm is practical and efficient.
منابع مشابه
A Space-Saving Approximation Algorithm for Grammar-Based Compression
A space-efficient approximation algorithm for the grammar-based compression problem, which requests for a given string to find a smallest context-free grammar deriving the string, is presented. For the input length n and an optimum CFG size g, the algorithm consumes only O(g log g) space and O(n log∗n) time to achieve O((log∗n) logn) approximation ratio to the optimum compression, where log∗n i...
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