design_circular_deque.py

class MyCircularDeque:

    def __init__(self, k: int):
#         front means left and rear mean right 
        self.deque = [0] * k
        self.front = 0
        self.rear = 0
        self.size = k
        self.curr_size = 0 
        
    def insertFront(self, value: int) -> bool:
        if self.isFull():
            return False
        if not self.isEmpty():
            self.front = ((self.front - 1) % self.size)
        self.deque[self.front] = value
        self.curr_size += 1
        return True
    
    def insertLast(self, value: int) -> bool:
        if self.isFull():
            return False
        if not self.isEmpty():
            self.rear = ((self.rear + 1) % self.size)
        self.deque[self.rear] = value
        self.curr_size += 1
        return True

    def deleteFront(self) -> bool:
        if self.isEmpty():
            return False
        self.front = ((self.front + 1) % self.size)
        self.curr_size -=1
        if self.isEmpty():
            self.front = self.rear
        return True

    def deleteLast(self) -> bool:
        if self.isEmpty():
            return False
        self.rear = ((self.rear - 1) % self.size)
        self.curr_size -=1
        if self.isEmpty():
            self.front = self.rear
        return True            

    def getFront(self) -> int:
        if self.isEmpty():
            return -1
        return self.deque[self.front]

    def getRear(self) -> int:
        if self.isEmpty():
            return -1
        return self.deque[self.rear]

    def isEmpty(self) -> bool:
        return self.curr_size == 0
    def isFull(self) -> bool:
        return self.curr_size == self.size