/* --- Function: void dequeue_node(Queue que) --- */
void dequeue_node(Queue que)
{
int tmp, *pi, *ptmp;
char mess[BUFSIZ], ans;
/* Initialize 'tmp'... */
tmp = 0;
do
{
if (tmp == -1)
break;
my_clearscrn();
printf("--- DEQUEUE NODE FROM QUEUE ---\n");
printf("\nCurrent queue status(%d nodes): ", QUEUEsize(que));
SLISTtraverse(que, print, SLIST_FWD);
ptmp = (int *)QUEUEpeek(que);
if (ptmp == NULL)
{
prompt_and_pause("\n\nQueue is EMPTY - nothing to do..!");
tmp = -1;
}
else
{
sprintf(mess, "\nAbout to dequeue node %d.. - Continue? (y/n): ", *ptmp);
ans = read_char(mess, 0, 0, my_chkch);
if (ans == 'y' || ans == 'Y')
{
if ((QUEUEdequeue(que, (void **)&pi)) != OK)
{
printf("\nFatal error dequeing data - exiting...!");
QUEUEdestroy(que);
exit(-1);
}
else
{
sprintf(mess, "Node %d will be dequeued!", *pi);
prompt_and_pause(mess);
my_destroy(pi);
}
}
else
tmp = -1;
}
} while (TRUE);
}
int main(void)
{
/* Declare YOUR variables here ! */
Stack mystk;
Queue myqueue;
char mess[BUFSIZ];
int i, nr;
srand((unsigned int)time(NULL));
my_clearscrn();
printf("--- INITIALIZING A QUEUE, %d ELEMENTS, RANDOM INTEGER DATA ---", NR_OF_ITEMS);
if ((myqueue = QUEUEinit(my_destroy)) == NULL) /* Initialize the queue... */
{
printf("\nFatal error - bailing out...!");
exit(-1);
}
queue_elements(myqueue, NR_OF_ITEMS); /* Populate the queue... */
nr = QUEUEsize(myqueue)/2; /* Save half the size of the queue... */
sprintf(mess, "\nNext - let's DEQUEUE %d elements from our queue...", nr);
prompt_and_pause(mess);
prompt_and_pause("...and now PUSH them - on a brand, new STACK...!!");
if ((mystk = STACKinit(my_destroy)) == NULL) /* Set up a new stack... */
{
printf("\nFatal error - bailing out...!");
exit(-1);
}
for (i = 0; i < nr; ++i)
{
void *piq, *pis;
int retval;
retval = QUEUEdequeue(myqueue, &piq);
assert(retval == OK);
sprintf(mess, "QUEUE: Dequeued: %02d (new frontvalue: %02d)", *(int *)piq, *(int *)QUEUEpeek(myqueue));
prompt_and_pause(mess);
/* Check current stack top... */
pis = STACKpeek(mystk);
/* Push the value just dequeued - from our queue... */
retval = STACKpush(mystk, piq);
assert(retval == OK);
if (pis == NULL) /* If this is the FIRST stack push... */
sprintf(mess, "STACK: Pushed : %02d (old stacktop : none)", *(int *)STACKpeek(mystk));
else
sprintf(mess, "STACK: Pushed : %02d (old stacktop : %02d)", *(int *)STACKpeek(mystk), *(int *)pis);
/* Print the message assembled above... */
prompt_and_pause(mess);
}
printf("\n--- CURRENT STATUS OF STACK AND QUEUE ---");
printf("\nStack: ");
SLISTtraverse(mystk, print, SLIST_FWD);
printf("\nQueue: ");
SLISTtraverse(myqueue, print, SLIST_FWD);
prompt_and_pause("\n\nLet's tidy up (destroy queue/stack) - Bye!");
SLISTdestroy(mystk);
SLISTdestroy(myqueue);
return 0;
}
