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class ImplementationOfDequeUsingCircularArray {
    private static final int MAX_SIZE = 100;
    private static int deque[];
    private static int front = -1;  //Initialize front to -1
    private static int rear = -1;   //Initialize rear to -1
 
    private static void insertFront(int x) {
        if (!isFull()) {
            if (front == -1) {  //Check if front==-1
                front = rear = 0;
                deque[front] = x;
            }
            else {
                if (front == 0) {
                    front = MAX_SIZE - 1;
                } else {
                    front--;  //Else decrement front by -1
                }
                deque[front] = x;
            }
        }
    }
    private static void insertRear(int x) {
        if (!isFull()) {
            if (rear == -1) { //Check if rear == -1
                front = rear = 0;
                deque[rear] = x;
            }
            else {
                if (rear == MAX_SIZE - 1) {
                    rear = 0;
                } else {
                    rear++; //Increment rear by 1
                }
                deque[rear] = x;
            }
        }
    }
    private static void deleteFront() {
        if (!isEmpty()) {
            if (front == rear) {
                front = rear = -1;
            }
            else {
                if (front == MAX_SIZE - 1) {
                    front = 0;
                } else {
                    front++;  //Increment front by 1
                }
            }
        }
    }
    private static void deleteRear() {
        if (!isEmpty()) {
            if (front == rear) {
                rear = front = -1;
            } 
           else {
                if (rear == 0) {
                    rear = MAX_SIZE - 1;
                } else {
                    rear--;  //Decrement rear by -1
                }
            }
        }
    }
    private static int getFront() {
        if (!isEmpty()) {
            return deque[front];
        }
        return -1;
    }
    private static int getRear() {
        if (!isEmpty()) {
            return deque[rear];
        }
        return -1;
    }
    private static boolean isEmpty() {
        if (front == -1) {
            return true;
        }
        return false;
    }
    private static boolean isFull() {
        if ((rear + 1) % MAX_SIZE == front) {
            return true;
        }
        return false;
    }
    public static void main(String[] args) {
         deque = new int[MAX_SIZE];
         
        insertFront(5);
        insertRear(10);
        insertRear(11);
        insertFront(19);
        System.out.pri