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/* LzHash.h -- HASH constants for LZ algorithms
2023-03-05 : Igor Pavlov : Public domain */
#ifndef ZIP7_INC_LZ_HASH_H
#define ZIP7_INC_LZ_HASH_H
/*
(kHash2Size >= (1 << 8)) : Required
(kHash3Size >= (1 << 16)) : Required
*/
#define kHash2Size (1 << 10)
#define kHash3Size (1 << 16)
// #define kHash4Size (1 << 20)
#define kFix3HashSize (kHash2Size)
#define kFix4HashSize (kHash2Size + kHash3Size)
// #define kFix5HashSize (kHash2Size + kHash3Size + kHash4Size)
/*
We use up to 3 crc values for hash:
crc0
crc1 << Shift_1
crc2 << Shift_2
(Shift_1 = 5) and (Shift_2 = 10) is good tradeoff.
Small values for Shift are not good for collision rate.
Big value for Shift_2 increases the minimum size
of hash table, that will be slow for small files.
*/
#define kLzHash_CrcShift_1 5
#define kLzHash_CrcShift_2 10
#endif
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