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#define _all5 0x55555555 | |
#define _all3 0x33333333 | |
#define _all0F 0x0F0F0F0F | |
#define _all01 0x01010101 | |
#define _to64(x) (((long long)x)<<32 + x) | |
int NumberOfSetBits64(long long i) | |
{ | |
i = i - ((i >> 1) & _to64(_all5)); | |
i = (i & _to64(_all3)) + ((i >> 2) & _to64(_all3)); | |
i = ((i + (i >> 4)) & _to64(_all0F)); | |
return (i*_to64(_all01))>>56; | |
} | |
int NumberOfSetBits32(int i) | |
{ | |
i = i - ((i >> 1) & _all5); | |
i = (i & _all3) + ((i >> 2) & _all3); | |
i = ((i + (i >> 4)) & _all0F); | |
return (i*(_all01))>>24; | |
} |
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