Fast skipping into text asset

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  1. euclidean

    euclidean New Member This Topic's Starter

    Aug 30, 2010
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    Hey, so, I'm working on a word game for Android and I'm currently trying to optimize my word validation code.

    There are something like 270,000 words in the English language and I need to be able to take a user-inputted word and confirm it is in this list very quickly. My goal is under 50ms.

    I've written a structure that indexes this list first by number of letters, then by first letter, then by every fiftieth word.

    My problem is that after I do this to get the number of bytes to skip in the appropriate word list text file, I call skip(int bytes) on my BufferedReader. Using the Android tracer, I can see that this call takes up 99.7% of the time spent validating a word - up to about 2 seconds in a worst case search. I figure this method is implemented by calling skip(), <bytes> times.

    So I am looking for a way to skip into an asset stream in constant time, like simply moving the read pointer by a specified number of bytes without actually reading.

    Is this even possible, or should I write a script that divides my word lists up into very small files with 50-100 words each?


  2. IanGClifton

    IanGClifton Well-Known Member

    Feb 7, 2010
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    I don't think you need to drop the file size down that small, but it would make sense to split it into several files so you're not having to skip a megabyte just to find the word you're looking for. Splitting this into ten files should give you a pretty big performance increase, but you can tweak the number to what works best for you.

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