C_PRG_LANG_EX_2.9

#include <stdio.h>

// Count amount of '1' bits
int bitcount(unsigned int x)
{
    int cnt ;

    for (cnt = 0;  x != 0; x &= (x - 1))
        cnt++;

    return cnt;
}

int main(void)
{
    int x, y;
    x = 2679;
    y = 1473;

    printf("bitcount for %i is %i\n", x, bitcount(x));
    printf("bitcount for %i is %i\n", y, bitcount(y));

    return 0;
}