Exemplo n.º 1
0
 def test_pop(self):
     h = MaxHeap(elements=to_add, do_copy=True)
     self.assertEqual(h.peek(), max(to_add))
     self.assertEqual(len(h), len(to_add))
     for i, v in enumerate(reversed(sorted(to_add))):
         print(i, v)
         self.assertEqual(h.pop(), v)
         self.assertEqual(len(h), len(to_add) - i - 1)
     self.assertEqual(len(h), 0)
     self.assertIsNone(h.pop())
     for i in range(len(to_add_2)):
         h.insert(to_add_2[i])
         self.assertEqual(h.peek(), max(to_add_2[:i + 1]))
         self.assertEqual(len(h), i + 1)
Exemplo n.º 2
0
class PriorityQueueHeap:
    "Implementation of a priority queue as a heap"

    # Reuse of elements used in tree implementation is inefficient
    # because we don't need  a linked list. Oh well.
    def __init__(self, vals=None, priorities=None):
        if priorities is not None and vals is not None:
            if len(priorities) != len(vals):
                raise ValueError("Must be as many priorities as values.")
            elements = [
                PriorityQueueElement(p, v) for v, p in zip(vals, priorities)
            ]
        else:
            elements = None
        self._h = MaxHeap(elements=elements)

    def insert(self, value, priority):
        element = PriorityQueueElement(priority, value)
        self._h.insert(element)

    def pop_max(self):
        element = self._h.pop()
        if element is None:
            return element
        return element.pop()

    def peek(self):
        element = self._h.peek()
        if element is None:
            return element
        return element.peek()

    def is_empty(self):
        return len(self) < 1

    def shrink_to_size(self):
        "Shrinks heap capacity to current size"
        self._h.shrink_to_size()

    def __len__(self):
        return len(self._h)
Exemplo n.º 3
0
 def test_insert(self):
     h = MaxHeap()
     for i in range(len(to_add)):
         h.insert(to_add[i])
         self.assertEqual(h.peek(), max(to_add[:i + 1]))
         self.assertEqual(len(h), i + 1)
Exemplo n.º 4
0
 def test_construct(self):
     h = MaxHeap(elements=to_add, do_copy=True)
     self.assertEqual(h.peek(), max(to_add))