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/*
* These hash functions were developed by Thomas Wang.
*
* http://www.concentric.net/~ttwang/tech/inthash.htm
*/
#include <stdint.h>
uint32_t hashable_wang_32(uint32_t a)
{
a = (a ^ 61) ^ (a >> 16);
a = a + (a << 3);
a = a ^ (a >> 4);
a = a * 0x27d4eb2d;
a = a ^ (a >> 15);
return a;
}
uint64_t hashable_wang_64(uint64_t key)
{
key = (~key) + (key << 21); // key = (key << 21) - key - 1;
key = key ^ ((key >> 24) | (key << 40));
key = (key + (key << 3)) + (key << 8); // key * 265
key = key ^ ((key >> 14) | (key << 50));
key = (key + (key << 2)) + (key << 4); // key * 21
key = key ^ ((key >> 28) | (key << 36));
key = key + (key << 31);
return key;
}
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