#include
#include
#define max 5
int q[10],front=0,rear=-1;
void main()
{
    int ch;
    void insert();
    void delet();
    void display();
    clrscr();
    printf("\nQueue operations\n");
    printf("1.insert\n2.delete\n3.display\n4.exit\n");
    while(1)
    {
        printf("Enter your choice:");
        scanf("%d",&ch);
        switch(ch)
        {
        case 1: insert();
            break;
        case 2: delet();
            break;
        case 3:display();
            break;
        case 4:exit();
        default:printf("Invalid option\n");
        }
    }
}

void insert()
{
    int x;
    if(rear==max-1)
        printf("Queue is overflow\n");
    else
    {
        printf("Enter element to be insert:");
        scanf("%d",&x);
        q[++rear]=x;
    }
}
void  delet()
{
    int a;
    if((front==0)&&(rear==-1))
    {
        printf("Queue is underflow\n");
        getch();
        exit();
    }
    a=q[front++];
    printf("Deleted element is:%d\n",a);
    if(front>rear)
    {
        front=0;
        rear=-1;
    }
}

void display()
{
    int i;
    if(front==0&&rear==-1)
    {
        printf("Queue is underflow\n");
        getch();
        exit();
    }
    for(i=front;i<=rear;i++)
        printf("\t%d",q[i]);
    printf("\n");
}
getch();

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