mirror of https://github.com/TheAlgorithms/C
51 lines
1017 B
C
51 lines
1017 B
C
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/**
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* @addtogroup hash Hash algorithms
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* @{
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* @file hash_djb2.c
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* @author [Christian Bender](https://github.com/christianbender)
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* @brief [DJB2 hash algorithm](http://www.cse.yorku.ca/~oz/hash.html)
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*/
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#include <assert.h>
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#include <inttypes.h>
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#include <stdio.h>
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/**
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* @brief DJB2 algorithm implementation
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*
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* @param s NULL terminated string to hash
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* @return 64-bit hash result
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*/
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uint64_t djb2(const char* s)
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{
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uint64_t hash = 5381; /* init value */
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size_t i = 0;
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while (s[i] != '\0')
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{
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hash = ((hash << 5) + hash) + s[i];
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i++;
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}
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return hash;
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}
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/**
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* Test function for ::djb2
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* \returns none
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*/
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void test_djb2(void)
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{
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assert(djb2("Hello World") == 13827776004929097857);
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assert(djb2("Hello World!") == 13594750393630990530);
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assert(djb2("Hello world") == 13827776004967047329);
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assert(djb2("Hello world!") == 13594750394883323106);
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printf("Tests passed\n");
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}
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/** @} */
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/** Main function */
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int main()
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{
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test_djb2();
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return 0;
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}
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