CircularQueue.py

class circularQueue:
    def __init__(self,size):
        # since python doesn`t have arrays i`m using list in place (by default a "list" is a linked list in python)
        self.arr = []
        
        self.head=0
        self.tail=0
        self.size=size
        for i in range(0,size):
            self.arr.append(None)
    
    def next(self,ptr):
        return (ptr+1) % (self.size)
    
    def isEmpty(self):
        return self.head == self.tail
    
    def isFull(self):
        return self.head == self.next(self.tail) 
        
    def push(self,e):
        if self.arr[self.tail] is None:
            self.arr[self.tail]=e
        if not self.isFull():
            self.tail = self.next(self.tail)
        print(f'push={e}\n {self.arr}\n head={self.head}\n tail={self.tail}\n')
        
    def pop(self):
        if not self.isEmpty():
            self.arr[self.head]=None
            if self.isFull():
                self.tail = self.next(self.tail)
            self.head=self.next(self.head)
        print(f'pop\n {self.arr}\n head={self.head}\n tail={self.tail}\n')

queue = circularQueue(4)
queue.push(1)
queue.push(2)
queue.push(3)
queue.push(4)
queue.push(5)
queue.pop()
queue.push(5)
queue.push(6)
queue.pop()
queue.push(6)
queue.push(6)