Queue Implementation using arrays

#include<stdio.h>
#include<stdlib.h>
#define MAX 4       //you can increase or decrease the
                    //queue size by modifying MAX value

void Enqueue(int Q[], int item);
void Dequeue(int Q[]);
void display_Q(int Q[]);

int Front=-1,Rear=-1;


int main(void)
{
    int item,choice;
    int Q[MAX];

    while(1)
    {
        printf("\n1.Insert an item into Q\n2.Delete an item from Q"
               "\n3.Display Queue\n4.Exit\n\nEnter the choice as given : ");
        scanf("%d",&choice);

        switch(choice)
        {
            case 1:printf("\nEnter the element : ");
                    scanf("%d",&item);
                    Enqueue(Q,item);
                    break;
            case 2:Dequeue(Q);
                    break;
            case 3:display_Q(Q);
                    break;
            case 4:exit(0);
                    break;
            default: printf("\n\nYou have entered wrong choice !\n\n");
        }
    }
    return 0;
}

void Enqueue(int Q[], int item)
{

    if(Rear == MAX-1)
    {
        if(Front == 0)
            printf("\nQueue is full, you can't enter any more elemetns !\n\n");
        else
            printf("\nYou can't insert untill queue will not be empty !\n");
    }
    else
    {
        Rear++;
        Q[Rear]= item;
        if(Front==-1)
            Front = 0;
    }
}

void Dequeue(int Q[])
{
    int x;
    if(Front == -1)
        printf("\nQueue is Empty, you can't delete any more element !\n\n");
    else
    {
        x = Q[Front];
        Front++;
        if(Front == Rear+1)
        {
            Front = -1;
            Rear = -1;
        }
        printf("\n%d is deleted form Queue !\n",x);
    }
}

void display_Q(int Q[])
{
    int i;
    if(Front == -1)
        printf("\nQueue is Empty !\n\n");
    else
        for(i=Front; i<=Rear; i++)
        printf(" %d",Q[i]);
}

//Note => once you started deletion You can't insert another
//element in queue untill the queue is empty.
//cause it is array implementation and it is also not a circular queue

Output: