/**
 * Get 8 3 bit numbers of the command line (ie, number in range 0-7)
 * and output the bit from those three numbers.
 * Either by printing the bits to the screen or by 
 * putting the bits into an unsigned char, then outputiong that 
 * char to the screen every time its gets all 8 bits filled.
 * 
 * This is an alternate version -- perhaps cleverer -- making better
 * use of masks.  Works by shifting the mask rather than shifting the number.
 * 
 * @author gtowell
 * Created: April 2021
 * Modified: May 2021
 * **/

#include <stdio.h>
#include <stdlib.h>
int main(int argc, char const *argv[])
{
    unsigned char output = 0;
    unsigned int res = 0;
    int placer = 1 << 7; // or just placer = 128;
    for (int i = 1; i <= 8; i++)
    {
        int num = atoi(argv[i]);
        int mask = 1 << 2; // or just mask = 4;
        for (int j = 0; j < 3; j++)
        {
            int v = (num & mask);
            printf("%d", v);
            if (v)
                output |= placer;
            mask >>= 1;
            placer >>= 1;
            if (!placer) {
                printf("\n%d\n", output);
                placer = 1 << 7;
                output = 0;
            }
        }
    }
    printf("\n");
    return 0;
}