La2_01.java

#include<stdio.h>
#define max 5
int queue[max];
int front=-1;
int rear=-1;
int isEmpty();
int isFull();
void insert(int);
int delete();
void traverse();
int main()
{
    int choice, item;
    do
    {
        printf("--Queue Operations--\n");
        printf("Press 1 to Insert\n");
        printf("Press 2 to Delete\n");
        printf("Press 3 to Traverse\n");
        printf("Press 4 for Exit\n");
        printf("Enter your choice:\n");
        scanf("%d", &choice);
        switch(choice)
        {
            case 1:
                printf("Enter the element to insert:\n");
                scanf("%d", &item);
                insert(item);
                break;
            case 2:
                item=delete();
                printf("Deleted element: %d\n", item);
                break;
            case 3:
                traverse();
                break;
            case 4:
                exit(0);
            default:
                printf("Invalid choice");
        }
    }
    while(choice>=1 && choice<=4);
}
int isEmpty()
{
    if(rear==-1)
        return 1;
    else
        return 0;
}
int isFull()
{
    if(rear==max-1)
        return 1;
    else
        return 0;
}
void insert(int item)
{
    if(isFull())
        printf("Queue is full\n");
    else
    {
        if(isEmpty())
            front=rear=0;
        else
            rear++;
        queue[rear]=item;
    }
}
int delete()
{
    int item;
    if(isEmpty())
        printf("Queue is empty\n");
    else
    {
        item=queue[front];
        if(front==rear)
            front=rear=-1;
        else
            front++;
    }
    return item;
}
void traverse()
{
    int i;
    if(isEmpty())
        printf("Queue is empty\n");
    else
    {
        printf("Queue contains ");
        for(i=front; i<=rear; i++)
            printf("%d ", queue[i]);
        printf("\n");
    }
}