#include<stdio.h>
#define size 100
int queue[size],x,y,z;
int front=-1,rear=-1;
int dequeue()
{
    if(rear==-1)
    {
        printf("underflow");
        exit(1);
    }
    else{
        front++;
        if(front>rear)
        {
            front=rear=-1;
        }
    }
}
void enqueue(int x)
{
    if(rear==size-1)
    {
        printf("overflow\n");
        exit(1);
    }
    if(front==-1)
    {
        front++;
    }
    rear++;
    queue[rear]=x;
}
void display()
{
    if(front==rear==-1)
        printf("queue empty\n");
    else
    {
        int i;
        for(i=front;i<=rear;i++)
        {
            printf("%d\n",queue[i]);
        }
    }
}
int main()
{
    printf("the queue is :");
    enqueue(1);
    enqueue(2);
        enqueue(90);
    dequeue();
    display();
}