859 Design Circular Deque
859 Design Circular Deque
Design Circular Deque 
Design your implementation of the circular double-ended queue (deque).
Implement the MyCircularDeque class:
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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:
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**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]
**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
Constraints:
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1 <= k <= 1000
0 <= value <= 1000
At most 2000 calls will be made to insertFront, insertLast, deleteFront, deleteLast, getFront, getRear, isEmpty, isFull.
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class MyCircularDeque:
def __init__(self, k: int):
self.arr = []
self.size = k
def insertFront(self, value: int) -> bool:
if len(self.arr) + 1 <= self.size:
self.arr = [value] + self.arr
return True
else:
return False
def insertLast(self, value: int) -> bool:
if len(self.arr) + 1 <= self.size:
self.arr.append(value)
return True
else:
return False
def deleteFront(self) -> bool:
if len(self.arr) - 1 >= 0:
self.arr.pop(0)
return True
else:
return False
def deleteLast(self) -> bool:
if len(self.arr) - 1 >= 0:
self.arr.pop()
return True
else:
return False
def getFront(self) -> int:
if len(self.arr) > 0:
return self.arr[0]
else:
return -1
def getRear(self) -> int:
if len(self.arr) > 0:
return self.arr[-1]
else:
return -1
def isEmpty(self) -> bool:
return len(self.arr) == 0
def isFull(self) -> bool:
return self.size == len(self.arr)
# Your MyCircularDeque object will be instantiated and called as such:
# obj = MyCircularDeque(k)
# param_1 = obj.insertFront(value)
# param_2 = obj.insertLast(value)
# param_3 = obj.deleteFront()
# param_4 = obj.deleteLast()
# param_5 = obj.getFront()
# param_6 = obj.getRear()
# param_7 = obj.isEmpty()
# param_8 = obj.isFull()
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