algorithm-in-python/dataStructure/circularQueue.py

class MyCircularQueue:

    def __init__(self, k):
        """
        Initialize your data structure here. Set the size of the queue to be k.
        :type k: int
        """
        self.size = k+1
        self.data = [0]*self.size
        self.head = self.rear = 0

    def enQueue(self, value):
        """
        Insert an element into the circular queue. Return true if the operation is successful.
        :type value: int
        :rtype: bool
        """
        if self.isFull():
            return False
        self.data[self.rear] = value
        self.rear = (self.rear+1)%self.size
        return True
    def deQueue(self):
        """
        Delete an element from the circular queue. Return true if the operation is successful.
        :rtype: bool
        """
        if self.isEmpty():
            return False
        self.head = (self.head+1)%self.size
        return True
        
    def Front(self):
        """
        Get the front item from the queue.
        :rtype: int
        """
        if self.isEmpty():
            return -1
        return self.data[self.head]
        

    def Rear(self):
        """
        Get the last item from the queue.
        :rtype: int
        """
        if self.isEmpty():
            return -1
        return self.data[(self.rear-1)%self.size]

    def isEmpty(self):
        """
        Checks whether the circular queue is empty or not.
        :rtype: bool
        """
        return self.head ==self.rear
        

    def isFull(self):
        """
        Checks whether the circular queue is full or not.
        :rtype: bool
        """
        return (self.head - self.rear)%self.size ==1
        


# Your MyCircularQueue object will be instantiated and called as such:
# obj = MyCircularQueue(k)
# param_1 = obj.enQueue(value)
# param_2 = obj.deQueue()
# param_3 = obj.Front()
# param_4 = obj.Rear()
# param_5 = obj.isEmpty()
# param_6 = obj.isFull()