designCircularQueue.cpp

#include <bits/stdc++.h>

using namespace std;

//   Design Circular Queue

class MyCircularQueue
{
    int *arr;
    int rear, front, capacity;

public:
    MyCircularQueue(int k)
    {
        capacity = k;
        arr = new int[capacity]{0};
        rear = front = -1;
    }

    bool enQueue(int value)
    {
        if (isFull())
            return false;
        rear = (rear + 1) % capacity;
        arr[rear] = value;
        front = (front == -1) ? 0 : front;
        return true;
    }

    bool deQueue()
    {
        if (isEmpty())
            return false;
        if (front == rear)
            front = rear = -1;
        else
            front = (front + 1) % capacity;
        return true;
    }

    int Front()
    {
        if (isEmpty())
            return -1;
        return arr[front];
    }

    int Rear()
    {
        if (isEmpty())
            return -1;
        return arr[rear];
    }

    bool isEmpty() { return front == -1; }

    bool isFull() { return (rear + 1) % capacity == front; }
};

/**
 * Your MyCircularQueue object will be instantiated and called as such:
 * MyCircularQueue* obj = new MyCircularQueue(k);
 * bool param_1 = obj->enQueue(value);
 * bool param_2 = obj->deQueue();
 * int param_3 = obj->Front();
 * int param_4 = obj->Rear();
 * bool param_5 = obj->isEmpty();
 * bool param_6 = obj->isFull();
 */