def TestBuildMaxHeap(self):
input = [random.randrange(100) for _ in range(100)]
h = MaxHeap(input)
sorted_input = sorted(input)
for i in reversed(range(len(input))):
self.assertEqual(h.peek_max(), sorted_input[i])
self.assertEqual(h.extract_max(), sorted_input[i])
def test_heap_invariant(self):
heap = MaxHeap([2,4,6,8,10,1,3,5,7,9])
for k in range(len(heap)):
if 2*k+1 < len(heap):
self.assertTrue(heap.get(k) >= heap.get(2*k+1))
if 2*k+2 < len(heap):
self.assertTrue(heap.get(k) >= heap.get(2*k+2))
def TestMaxHeapWithRandomInput(self):
input = [random.randrange(100) for _ in range(100)]
h = MaxHeap()
for num in input:
h.insert(num)
sorted_input = sorted(input)
for i in reversed(range(len(input))):
self.assertEqual(h.extract_max(), sorted_input[i])
def test_max_heap_has_max_at_top(self):
maxHeap = MaxHeap()
maxHeap.push(2)
maxHeap.push(10)
maxHeap.push(20)
maxHeap.push(1)
r = maxHeap.peek()
self.assertEqual(20, maxHeap.peek())
self.assertEqual(r, 20)
def full_max_heap():
test_heap = MaxHeap()
test_heap.add(4)
test_heap.add(6)
test_heap.add(3)
test_heap.add(7)
test_heap.add(5)
return test_heap
def calculate_medians_with_heaps(numbers):
"""Calculate the sum of all 10,000 medians, modulo 10000"""
max_heap = MaxHeap() # For storing the smaller half of numbers
min_heap = MinHeap() # For storing the larger half of numbers
medians = []
for number in numbers:
if max_heap.peek_max() is None or max_heap.peek_max() > number:
max_heap.insert(number)
if max_heap.size > min_heap.size + 1:
min_heap.insert(max_heap.extract_max())
else:
min_heap.insert(number)
if min_heap.size > max_heap.size + 1:
max_heap.insert(min_heap.extract_min())
if max_heap.size >= min_heap.size:
medians.append(max_heap.peek_max())
else:
medians.append(min_heap.peek_min())
return medians
class BuildingMap:
def __init__(self):
self.map = defaultdict(list)
self.heap = MaxHeap()
def put(self, height):
self.heap.push(height)
self.map[height].append(height)
def remove(self, height):
if height not in self.map:
print(f'height {height} not in map')
return
n = self.map[height].pop()
self.heap.remove(n)
if len(self.map[height]) == 0:
self.map.pop(height)
def getMax(self):
if self.heap.empty():
return 0
return self.heap.peek()
def TestSizeReducedAfterExtractMax(self):
input = [6, 1, 4, 5, 3, 2]
h = MaxHeap()
for num in input:
h.insert(num)
initial_size = h.size
self.assertEqual(initial_size, len(h.a))
h.extract_max()
self.assertEqual(initial_size - 1, h.size)
def find_k_smallest(a, k):
h = MaxHeap()
for i in range(len(a)):
if i < k:
h.push(a[i])
elif a[i] < h.peek():
popped = h.pop()
h.push(a[i])
return h.getItems()
h = []
heapq.heapify(h)
for i in range(len(a)):
if i < k:
heapq.heappush(h, -a[i])
elif a[i] < -h[0]:
heapq.heapreplace(h, -a[i])
return [-i for i in h]
def test_it_can_make_heaps(self):
minHeap = MinHeap()
self.assertIsInstance(minHeap, MinHeap)
maxHeap = MaxHeap()
self.assertIsInstance(maxHeap, MaxHeap)
def test_max_heap_max_is_retained(self):
maxHeap = MaxHeap()
maxHeap.push(7)
maxHeap.push(4)
maxHeap.push(10)
maxHeap.push(6)
maxHeap.push(5)
self.assertEqual(10, maxHeap.peek())
maxHeap.remove(10)
self.assertEqual(7, maxHeap.peek())
maxHeap.remove(6)
self.assertEqual(7, maxHeap.peek())
def test_heaps_empty(self):
maxHeap = MaxHeap()
self.assertEqual(True, maxHeap.empty())
def __init__(self):
self.map = defaultdict(list)
self.heap = MaxHeap()
def TestMaxHeapProperty(self):
input = [6, 1, 4, 5, 3, 2]
h = MaxHeap()
for num in input:
h.insert(num)
self.assertEqual(h.extract_max(), 6)
def test_initialize(self):
heap = MaxHeap([2,4,6,8,10,1,3,5,7,9])
self.assertEquals(heap.get(0), 10)
def init_max_heap():
test_heap = MaxHeap()
return test_heap
