python 自定义优先级队列

• 2019 年 10 月 7 日
• 筆記

priorityQueue

import heapq

class PriorityQueue: def init(self): self._queue = [] self._index = 0

def push(self, item, priority):      heapq.heappush(self._queue, (-priority, self._index, item))      self._index += 1    def pop(self):      return heapq.heappop(self._queue)[-1]

push,pop

class Item: … def init(self, name): … self.name = name … def repr(self): … return 'Item({!r})'.format(self.name) … q = PriorityQueue() q.push(Item('foo'), 1) q.push(Item('bar'), 5) q.push(Item('spam'), 4) q.push(Item('grok'), 1) q.pop() Item('bar') q.pop() Item('spam') q.pop() Item('foo') q.pop() Item('grok')