如何實現簡單的位數組(bit array)

#include "limits.h"#defineBITMASK(b) (1 << ((b) % CHAR_BIT))#defineBITSLOT(b) ((b) / CHAR_BIT)#defineBITSET(a, b) ((a)[BITSLOT(b)] |= BITMASK(b))#defineBITCLEAR(a, b) ((a)[BITSLOT(b)] &= ~BITMASK(b))#defineBITTEST(a, b) ((a)[BITSLOT(b)] & BITMASK(b))#defineBITNSLOTS(nb) ((nb + CHAR_BIT - 1) / CHAR_BIT)

charbitarray[BITNSLOTS(50)];

BITSET(bitarray,23);

if(BITTEST(bitarray,35)) ...

for(i =0; i < BITNSLOTS(47); i++)array3[i]= array1[i] | array2[i];

for(i =0; i < BITNSLOTS(47); i++)array3[i]= array1[i] & array2[i];

#include#include<string.h>#defineMAX 10000intmain(){charbitarray[BITNSLOTS(MAX)];inti, j;memset(bitarray,0, BITNSLOTS(MAX));for(i =2; i < MAX; i++){if(!BITTEST(bitarray, i)){printf("%d", i);for(j = i + i; j < MAX; j +=i)BITSET(bitarray, j);}}return0;}