Java Implementation

public class LinearQueue {
    private String[] queue;
    private int front, rear, maxSize;

    public LinearQueue(int size) {
        maxSize = size;
        queue = new String[maxSize];
        front = 0;  rear = -1;
    }

    public void enqueue(String item) {
        if (rear >= maxSize - 1) {
            System.out.println("Queue is full");
        } else {
            rear++;
            queue[rear] = item;
        }
    }

    public String dequeue() {
        if (front > rear) {
            System.out.println("Queue is empty");
            return "";
        }
        String item = queue[front];
        front++;
        return item;
    }

    public boolean isEmpty() { return front > rear; }
    public boolean isFull()  { return rear >= maxSize - 1; }
}

public class CircularQueue {
    private String[] queue;
    private int front, rear, size, maxSize;

    public CircularQueue(int capacity) {
        maxSize = capacity;
        queue = new String[maxSize];
        front = 0;  rear = -1;  size = 0;
    }

    public void enqueue(String item) {
        if (size >= maxSize) {
            System.out.println("Queue is full");
        } else {
            rear = (rear + 1) % maxSize;  // MOD wrap-around
            queue[rear] = item;
            size++;
        }
    }

    public String dequeue() {
        if (size == 0) {
            System.out.println("Queue is empty");
            return "";
        }
        String item = queue[front];
        front = (front + 1) % maxSize;  // MOD wrap-around
        size--;
        return item;
    }

    public boolean isEmpty() { return size == 0; }
    public boolean isFull()  { return size >= maxSize; }
}

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