Romb - KZ 2018

#include <stdio.h>
#include <stdint.h>

#define ITER 8

void pbyte(uint8_t x)
{
    for (uint8_t i = 0; i < 8; i++)
        printf("%d", ((x << i) & 0x80) ? 1 : 0);
}

uint8_t reverse(uint8_t x)
{
    uint8_t out = 0;
    for (uint8_t i = 0; i < 8; i++) {
        out = (out << 1) | (x & 0b1);
        x >>= 1;
    }
    return out;
}

static uint8_t t = 0;

void mod(void)
{
   static uint8_t flag = 0;

   if (!t) {
       t = 0x18;
       flag = flag ? 0 : 1;
       return;
   }
   else if (t == 0x18 && !flag) {
       t = 0x00;
       return;
   }
   else if (t == 0x81)
        flag = flag ? 0 : 1;

   t &= 0x0F;
   if (flag)
       t >>= 1;
   else
       t <<= 1;

   t |=  reverse(t);
}

int main(void)
{

    uint8_t n = 2;
    for (uint8_t i = 0; i < n * ITER; i++) {
        pbyte(t);
        printf("\n");
        mod();
    }

    return 0;
}