标签:循环 too col 提示 ram 并且 des 头部 长度
设计你的循环队列实现。 循环队列是一种线性数据结构,其操作表现基于 FIFO(先进先出)原则并且队尾被连接在队首之后以形成一个循环。它也被称为“环形缓冲器”。
循环队列的一个好处是我们可以利用这个队列之前用过的空间。在一个普通队列里,一旦一个队列满了,我们就不能插入下一个元素,即使在队列前面仍有空间。但是使用循环队列,我们能使用这些空间去存储新的值。
你的实现应该支持如下操作:
MyCircularQueue(k)
: 构造器,设置队列长度为 k 。Front
: 从队首获取元素。如果队列为空,返回 -1 。Rear
: 获取队尾元素。如果队列为空,返回 -1 。enQueue(value)
: 向循环队列插入一个元素。如果成功插入则返回真。deQueue()
: 从循环队列中删除一个元素。如果成功删除则返回真。isEmpty()
: 检查循环队列是否为空。isFull()
: 检查循环队列是否已满。
示例:
MyCircularQueue circularQueue = new MycircularQueue(3); // 设置长度为 3 circularQueue.enQueue(1); // 返回 true circularQueue.enQueue(2); // 返回 true circularQueue.enQueue(3); // 返回 true circularQueue.enQueue(4); // 返回 false,队列已满 circularQueue.Rear(); // 返回 3 circularQueue.isFull(); // 返回 true circularQueue.deQueue(); // 返回 true circularQueue.enQueue(4); // 返回 true circularQueue.Rear(); // 返回 4
提示:
from collections import deque class MyCircularQueue: def __init__(self, k: int): """ Initialize your data structure here. Set the size of the queue to be k. """ self.size = k self.q = deque(maxlen=k) 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 self.q.append(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 self.q.popleft() return True def Front(self) -> int: """ Get the front item from the queue. """ if self.isEmpty(): return -1 return self.q[0] def Rear(self) -> int: """ Get the last item from the queue. """ if self.isEmpty(): return -1 return self.q[-1] def isEmpty(self) -> bool: """ Checks whether the circular queue is empty or not. """ return len(self.q) == 0 def isFull(self) -> bool: """ Checks whether the circular queue is full or not. """ return len(self.q) == self.size # Your MyCircularQueue object will be instantiated and called as such: # obj = MyCircularQueue(k) # param_1 = obj.enQueue(value) # param_2 = obj.deQueue() # param_3 = obj.Front() # param_4 = obj.Rear() # param_5 = obj.isEmpty() # param_6 = obj.isFull()
设计实现双端队列。
你的实现需要支持以下操作:
示例:
MyCircularDeque circularDeque = new MycircularDeque(3); // 设置容量大小为3 circularDeque.insertLast(1); // 返回 true circularDeque.insertLast(2); // 返回 true circularDeque.insertFront(3); // 返回 true circularDeque.insertFront(4); // 已经满了,返回 false circularDeque.getRear(); // 返回 2 circularDeque.isFull(); // 返回 true circularDeque.deleteLast(); // 返回 true circularDeque.insertFront(4); // 返回 true circularDeque.getFront(); // 返回 4
提示:
from collections import deque class MyCircularDeque: def __init__(self, k: int): """ Initialize your data structure here. Set the size of the deque to be k. """ self.cap = k self.q = deque(maxlen=k) def insertFront(self, value: int) -> bool: """ Adds an item at the front of Deque. Return true if the operation is successful. """ if len(self.q) < self.cap: self.q.appendleft(value) return True return False def insertLast(self, value: int) -> bool: """ Adds an item at the rear of Deque. Return true if the operation is successful. """ if len(self.q) < self.cap: self.q.append(value) return True return False def deleteFront(self) -> bool: """ Deletes an item from the front of Deque. Return true if the operation is successful. """ if self.isEmpty(): return False self.q.popleft() return True def deleteLast(self) -> bool: """ Deletes an item from the rear of Deque. Return true if the operation is successful. """ if self.isEmpty(): return False self.q.pop() return True def getFront(self) -> int: """ Get the front item from the deque. """ if self.isEmpty(): return -1 return self.q[0] def getRear(self) -> int: """ Get the last item from the deque. """ if self.isEmpty(): return -1 return self.q[-1] def isEmpty(self) -> bool: """ Checks whether the circular deque is empty or not. """ return len(self.q) == 0 def isFull(self) -> bool: """ Checks whether the circular deque is full or not. """ return len(self.q) == self.cap # 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()
设计循环队列——写起来最清爽的还使用原生的deque 双端队列
标签:循环 too col 提示 ram 并且 des 头部 长度
原文地址:https://www.cnblogs.com/bonelee/p/12545559.html