to Windows-1251 using a lookup table between the two encodings, but the modern approach is to convert the KOI8-R file to Unicode first and from that to Windows-1251. This is a more manageable approach; rather than needing lookup tables for all possible pairs of character encodings, an application needs only one lookup table for each character set, which it uses to convert to and from Unicode, thereby scaling the number of tables down from hundreds to a few tens.

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