Circular Queue

class MyCircularQueue:
 
    def __init__(self, k: int):
        """
        Initialize your data structure here. Set the size of the queue to be k.
        """
        self.head = -1
        self.tail = -1
        self.size = k
        self.queue = [None] * self.size
 
    def enQueue(self, value: int) -> bool:
        """
        Insert an element into the circular queue. Return true if the operation is successful.
        """
        if self.isFull():
            return False
 
        if self.isEmpty():
            self.head = 0
 
        self.tail = (self.tail + 1) % self.size
        self.queue[self.tail] = value
        return True
 
    def deQueue(self) -> bool:
        """
        Delete an element from the circular queue. Return true if the operation is successful.
        """
        if self.isEmpty():
            return False
 
        if self.head == self.tail:
            self.head = -1
            self.tail = -1
            return True
 
        self.queue[self.head] = None
        self.head = (self.head + 1) % self.size
        return True
 
    def Front(self) -> int:
        """
        Get the front item from the queue.
        """
        if self.isEmpty():
            return -1
 
        return self.queue[self.head]
 
    def Rear(self) -> int:
        """
        Get the last item from the queue.
        """
        if self.isEmpty():
            return -1
 
        return self.queue[self.tail]
 
    def isEmpty(self) -> bool:
        """
        Checks whether the circular queue is empty or not.
        """
        return self.head == -1
 
    def isFull(self) -> bool:
        """
        Checks whether the circular queue is full or not.
        """
        return (self.tail + 1) % self.size == self.head

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