test 3

#include<stdio.h>
#include<stdlib.h>

struct Node {
    int Data;
    struct Node *next;
} *rear, *front;

void delQueue()
{
    struct Node *temp, *var = rear;
    if (var == rear)
    {
        rear = rear->next;
        free(var);
    }
    else
        printf("\nQueue Empty");
}

void push(int value)
{
    struct Node *temp;
    temp = (struct Node *) malloc(sizeof(struct Node));
    temp->Data = value;
    if (front == NULL)
    {
        front = temp;
        front->next = NULL;
        rear = front;
    }
    else
    {
        front->next = temp;
        front = temp;
        front->next = rear;
    }
}

void display()
{
    struct Node *var = rear;
    if (var != NULL)
    {
        printf("\nElements are as:  ");
        while (var != front)
        {
            printf("\t%d", var->Data);
            var = var->next;
        }
        if (var == front)
        {
            printf("\t%d", var->Data);
        }
        printf("\n");
    }
    else
        printf("\nQueue is Empty");
}

int main()
{
    int i = 0;
    front = NULL;
    printf("\n1. Push to Queue");
    printf("\n2. Pop from Queue");
    printf("\n3. Display Data of Queue");
    printf("\n4. Exit\n");
    while (1)
    {
        printf(" \nChoose Option: ");
        scanf("%d", &i);
        switch (i)
        {
            case 1:
            {
                int value;
                printf("\nEnter a value to push into Queue: ");
                scanf("%d", &value);
                push(value);
                display();
                break;
            }
            case 2:
            {
                delQueue();
                display();
                break;
            }
            case 3:
            {
                display();
                break;
            }
            case 4:
            {
                exit(0);
            }
            default:
            {
                printf("\nWrong choice for operation");
            }
        }
    }
}