#include <conio.h>
#include <stdio.h>
#include <locale.h>
#include <windows.h>

const UCHAR N = 3, Q_EMPTY = 2, Q_FULL = 1;

struct queue
{
   UCHAR begin = 0, end = 0;
   LONGLONG data[N] = { 0 };
};

UCHAR push(queue &q, LONGLONG elem);
UCHAR pop(queue &q, LONGLONG &elem);

bool is_empty(queue q);
bool is_full(queue q);

void clear(queue &q);
void print(queue q);

int main()
{
   queue Q;

   return 0 * _getch();
}

UCHAR push(queue &q, LONGLONG elem)
{
   bool is_f = is_pfull(q);
   
   if (!is_f)
   {
      q.end++;
      q.data[q.end] = elem;
   }

   return is_f ? Q_FULL : 0;
}
UCHAR pop(queue &q, LONGLONG &elem)
{
   bool is_e = is_empty(q);

   if (!is_e)
   {
      elem = q.data[q.begin];
      q.data[q.begin] = 0;

      q.begin++;
   }

   return is_e ? Q_EMPTY : 0;
}

bool is_empty(queue q)
{
   return q.end == q.begin;
}
bool is_full(queue q)
{
   return q.end == N -1 && q.begin == 0;
}
bool is_pfull(queue q)
{
   return q.end == N - 1 && q.begin;
}

void clear(queue &q)
{
   for (LONGLONG n = 0; !is_empty(q); pop(q, n));
}
void print(queue q)
{
   LONGLONG n = 0;
   while (!is_empty(q))
   {
      pop(q, n);
      printf_s("%lld", n);
   }
}