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Thread: LZ77: why often possible to increase the match length to the left?

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    Member lz77's Avatar
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    Question LZ77: why often possible to increase the match length to the left?

    Why even if we have a hash table of 128K cells and remember hash for each position can often be done subj?
    For example: let we found match from current position for substring 'abcd' in string ...zabcd..., then we found that 'zabcd' also matches.
    Sorry for my English...

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    Administrator Shelwien's Avatar
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    Fast encoding strategies like to skip hashing inside of matches.

    Otherwise, you can just get collisions for hash values - its easily possible that the cell for 'zabc' would be overwritten, while the cell for 'abcd' won't.

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    lz77 (1st June 2020)

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