Queue implementation

Code:

#include<stdio.h>
#include<stdlib.h>
struct queue
{
	int n;
	struct queue *next;
};
struct queue *q;
void push();
void pop();
void show();
int main()
{
	int op;
	q=NULL;
	while(1)
	{
		printf("MENU OF QUEUE OPTIONS\n");
		printf("1.Push\n2.Pop\n3.Show\n4.Exit\n");
		printf("CHOOSE AN OPTION!\n");
		scanf("%d",&op);
		switch(op)
		{
			case 1: push();
				break;
			case 2: pop();
				break;
			case 3: system("CLS");show();
				break;
			case 4: exit(1);
			default: printf("NOT A VALID OPTION!\n");break;
		}
	}
	getch();
}
void pop()
{
	struct queue *t;
	t=q;
	if(t==NULL)
	{
		printf("QUEUE IS EMPTY!\n");
		return 0;
	}
	q=q->next;
	free(t);
	t=NULL;
}
void show()
{
	struct queue *t;
	t=q;
	if(t==NULL)
	{
		printf("QUEUE IS EMPTY!\n");
		return 0;
	}
	while(1)
	{
		printf("%d\n",t->n);
		if(t->next==NULL)
			break;
		t=t->next;
	}
}
void push()
{
	int num;
	struct queue *t;
	t=q;
    printf("ENTER A NUMBER TO PUSH!\n");
	scanf("%d",&num);
	if(t==NULL)
	{
		t=(struct queue *)malloc(sizeof(struct queue));
		t->n=num;
		t->next=NULL;
		q=t;
	}
	else
	{
		while(1)
		{
			if(t->next==NULL)
			{
				t->next=(struct queue *)malloc(sizeof(struct queue));
				t=t->next;
				t->n=num;
				t->next=NULL;
				break;
				
			}
			t=t->next;
		}
	}
}

Hello all, I just finished writing this program based on theory (FIRST IN FIRST OUT). Anyway my question is that is the above program considered a queue. The program in the book is very different from what i have written. I compiled it and it runs fine, but i just wanted to know if it is considered a queue.

Thank You !

As far as I can see yes, http://en.wikipedia.org/wiki/Queue_%28data_structure%29

I'd be very cautious about using while(1) ...

Code:

while(1)
{
    printf("%d\n",t->n);

    if(t->next==NULL)
        break;

    t=t->next;
}

Can be written as

Code:

do
{
    printf("%d\n", t->n);
    t = t->next;
} while(t != NULL);

You can probably see the latter is nicer on the eyes

Try bumping up the warning level when you compile, you'll see a few.

return 0; from void function (or something like that)

You can't return values from void functions.