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 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())
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 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]
