De-Que

#include <cstdio>
#include <cstdlib>
#define MAX 5

int Q[MAX];
int front = -1;
int rear = -1;
int Rfront = MAX;
int Rrear = MAX;
int count = 0;

int isEmpty() {
    if (count == 0)
        return 1;
    else
        return 0;
}

int isFull() {
    if (count == MAX)
        return 1;
    else
        return 0;
}

void display() {
    int i, j;
    if (count) {
        for (i = 0; i <= rear; i++)
            printf("%d ", Q[i]);
        printf("\n");
        for (i = MAX - 1; i >= Rrear; i--)
            printf("%d ", Q[i]);
        printf("\n\n");
    }
    else printf("Queue is Empty\n\n");
}


void enqueue(int x) {
    int choice;
    printf("1. Front-End\n");
    printf("2. Back-End\n");
    printf("Choice: ");
    scanf("%d", &choice);
    if (isFull())
        printf("Cannot Enqueue.\nOverflow\n\n");
    else {
        if (choice == 1) {
            Q[++rear] = x;
            if (front == -1) front++;
        }
        else if (choice == 2) {
            Q[--Rrear] = x;
            if (Rfront == MAX) Rfront--;
        }
        count++;
    }
    display();
}

void dequeue() {
    int choice;
    printf("1. Front-End\n");
    printf("2. Back-End\n");
    printf("Choice: ");
    scanf("%d", &choice);

    if (choice == 1) {
        if (rear >= 0) {
            rear--;
            count--;
        }
        else {
            printf("Cannot Dequeue\n");
            printf("Queue is Empty/Underflow\n\n");
        }
    }
    else if (choice == 2) {
        if (Rrear < MAX) {
            Rrear++;
            count--;
        }
        else {
            printf("Cannot Dequeue\n");
            printf("Queue is Empty/Underflow\n\n");
        }
    }
    if (isEmpty()) {
        front = -1;
        Rfront = MAX;
    }
    display();
}


int main() {
    int choice, value;
    while (1) {
        printf("1 En-queue\n");
        printf("2 De-queue\n");
        printf("3 Is-Empty\n");
        printf("4 Is-Full\n");
        printf("5 Exit\n");

        printf("Choice: ");
        scanf("%d", &choice);

        switch (choice) {
            case 1: {
                printf("Enter Value to En-queue: ");
                scanf("%d", &value);
                enqueue(value);
                break;
            }
            case 2: {
                dequeue();
                break;
            }
            case 3: {
                if (isEmpty())
                    printf("True\n\n");
                else
                    printf("False\n\n");
                break;
            }
            case 4: {
                if (isFull())
                    printf("True\n\n");
                else
                    printf("False\n\n");
                break;
            }
            case 5: {
                exit(0);
                break;
            }
            default: {
                printf("Invalid Choice\nTry Again\n\n");
            }
        }
    }
    return 0;
}