Queue

#include<stdio.h>
#include<stdlib.h>
#define MAX 100
int arr[MAX],front=-1,rear=-1;

void enqueue()
{
    int data,i,n;
    printf("How many element you want to add: ");
    scanf("%d", &n);
    for(i=0; i<n; i++)
    {
        printf("Enter data: ");
        scanf("%d", &data);
        if(i==0 && front==-1)
        {
            front++;
            rear++;
            arr[rear]=data;
        }
        else
        {
            rear++;
            arr[rear]=data;
        }
    }
}

void dequeue()
{
    int i;
    for(i=front; i<rear; i++)
    {
        arr[i]=arr[i+1];
    }
    rear--;
    printf("Done!");
}

void display()
{
    int i;
    for(i=front; i<=rear; i++)
    {
        printf("%d\t", arr[i]);
    }
}

void size()
{
    int i;
    for(i=front; i<=rear; i++);
    printf("Queue size: %d", i);
}


int main()
{
    int choice,m,n;
    while(1)
    {
        printf("\n\n\n");
        printf("1.Add an element to the queue\n");
        printf("2.Delete an element from the queue\n");
        printf("3.Display the queue\n");
        printf("4.View size of the queue\n");
        printf("5.Quit\n");
        printf("\nEnter your choice: ");
        scanf("%d", &choice);
        switch(choice)
        {
        case 1:
            enqueue();
            printf("Element added successfully!\n");
            break;
        case 2:
            dequeue();
            break;
        case 3:
            display();
            break;
        case 4:
            size();
            break;
        case 5:
            exit(0);
        default:
            printf ("\n\nWrong choice");
        }
    }
}