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in reply to Quantitative Change instead of Boolean

just for me to understand:

you said "Minus a certain amount of fudging to make sure things like revolving web ads don't mess me up."

how do you do this using MD5. i mean, changing one bit in the data will result in a totally different MD5 digest, won't it?
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Re^2: Quantitative Change instead of Boolean
by ikegami (Patriarch) on Jun 29, 2006 at 07:10 UTC
    He always removes the ads before using MD5. If the only difference between the page and its previously downloaded version are the ads, the MD5 digest will match. The pages aren't being compared; the pages without the ads are being compared.