frontier.py

from collections import deque
from heapq import *

class Queue:
    def __init__(self, *elements):
        self._elements = deque(elements)
        self._maxSize = len(self._elements)

    def __len__(self):
        return len(self._elements)

    def push(self, element):
        self._elements.append(element)
        self._maxSize = max(self._maxSize, len(self._elements))

    def pop(self):
        return self._elements.popleft()

    def max(self):
        return self._maxSize


class Stack(Queue):
    def pop(self):
        return self._elements.pop()

class Heap:
    def __init__(self):
        self._elements = []

    def __len__(self):
        return len(self._elements)

    def push(self, element):
        heappush(self._elements, element)

    def pop(self):
        return heappop(self._elements)