item,priority):# 将优先级反向存储,以便小顶堆可以实现大优先级heapq.heappush(self.elements,(priority,item))defget(self):returnheapq.heappop(self.elements)[1]defpeek(self):returnself.elements[0][1]ifself.elementselseNone
raise IndexError("pop from empty stack") def peek(self): if not self.is_empty(): return self.items[-1] else: return None def size(self): return len(self.items) def is_balanced(parentheses): stack = Stack() for p in parentheses: if p in "([{": stack.push(p) elif p in ")...
process process = readyQueue.peek(); System.out.println("进程" + process.id + "执行"); time++; process.exeTime++; //进程完成 if (process.exeTime == process.time) { process = readyQueue.poll(); endQueue.offer(process); process.roundTime = time - process.arriveTime; process.finshTime...
raise IndexError("Queue underflow")return self.myque.popleft()def peek(self):x = self.dequeue(...
print('Highest priority is ', pq.pop()) print('nr items is queue = ', len(pq)) # look at next highest but don't pop from queue print('Next highest is',pq.peek()) print('nr items is queue = ', len(pq)) Boltons 是一个纯 Python工具集...
parent = floor(i / 2)left = 2*iright = 2*i + 1 实现 实现一个最大堆：class MaxHeap: def __init__(self): self.data = [None]is_empty() —— 判断堆是否为空get_size() —— 获取堆中的元素个数peek_max() —— 返回堆顶元素，但不删除insert(value) —— 向堆中插入元素 def...
代码语言:javascript 复制 deftest_priority_queue():pq=PriorityQueue()pq.push(1)pq.push(3)pq.push(2)assert pq assert pq.peek()==1assert pq.pop()==1assert pq.peek()==2assert pq.remove(3)is None assert pq assert pq.peek()==2
1.使用Queue.LifoQueue(maxsize=0),他的原理我感觉其实和栈没有什么区别。 2.自己写一个栈 类实现 : classStack(object):# 初始化栈为空列表def__init__(self): self.items = []# 判断栈是否为空,返回布尔值defis_empty(self):returnself.items == []# 返回栈顶元素defpeek(self):returnself.items...
在Python 中 Queue 模块提供了一个同步的线程安全的队列类,它包括常见的 FIFO(先入先出)、LIFO(后入先出)、PriorityQueue(按优先级队列)以及先入先出类型的简单队列(SimpleQueue)。 1)LILO 先进先出,只能在尾部插入元素,只能从头部取出元素。 from queue import Queue ...
31 queue.peek()只是看这个值,并没有删除这个值的意思 30 Manhattan distance: 曼哈顿距离,两点之间南北方向和东西方向的距离之和 29 迷宫问题:maze problem 28 perfect binary tree:all leaf nodes at the same level, and all internal node has degree 2; full binary tree: each node has zero or two ch...