#641

Design Circular Deque

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Description

Design your implementation of the circular double-ended queue (deque).

Implement the MyCircularDeque class:

- MyCircularDeque(int k) Initializes the deque with a maximum size of k.

- boolean insertFront() Adds an item at the front of Deque. Returns true if the operation is successful, or false otherwise.

- boolean insertLast() Adds an item at the rear of Deque. Returns true if the operation is successful, or false otherwise.

- boolean deleteFront() Deletes an item from the front of Deque. Returns true if the operation is successful, or false otherwise.

- boolean deleteLast() Deletes an item from the rear of Deque. Returns true if the operation is successful, or false otherwise.

- int getFront() Returns the front item from the Deque. Returns -1 if the deque is empty.

- int getRear() Returns the last item from Deque. Returns -1 if the deque is empty.

- boolean isEmpty() Returns true if the deque is empty, or false otherwise.

- boolean isFull() Returns true if the deque is full, or false otherwise.

Example 1:

Input

["MyCircularDeque", "insertLast", "insertLast", "insertFront", "insertFront", "getRear", "isFull", "deleteLast", "insertFront", "getFront"]

[[3], [1], [2], [3], [4], [], [], [], [4], []]

Output

[null, true, true, true, false, 2, true, true, true, 4]

Example 2:

Explanation

MyCircularDeque myCircularDeque = new MyCircularDeque(3);

myCircularDeque.insertLast(1); // return True

myCircularDeque.insertLast(2); // return True

myCircularDeque.insertFront(3); // return True

myCircularDeque.insertFront(4); // return False, the queue is full.

myCircularDeque.getRear(); // return 2

myCircularDeque.isFull(); // return True

myCircularDeque.deleteLast(); // return True

myCircularDeque.insertFront(4); // return True

myCircularDeque.getFront(); // return 4

Solution