def getSkyline(self, buildings):
"""
:type buildings: List[List[int]]
:rtype: List[List[int]]
"""
if len(buildings) <= 0:
return
data = [[build[0], build[2], 0] for build in buildings]
data += [[build[1], build[2], 1] for build in buildings]
data = sorted(data, key=lambda x: (x[0], x[1]))
print data
heap = MaxHeap()
print heap.size()
result = []
for item in data:
x, h, tag = item[0:]
pre_height = -heap.top() if heap.size() > 0 else 0
if tag == 0:
heap.add(-h) #top is the lowest height
print 'push', -h
else:
print 'pop', heap.top()
heap.pop() #pop the lowest height
cur_height = -heap.top() if heap.size() > 0 else 0
if tag == 0 and cur_height > pre_height:
result.append([x, h])
elif tag == 1 and h > cur_height:
result.append([x, cur_height])
print item, pre_height, cur_height, result
return result
def test_is_empty(self):
heap = MaxHeap()
assert heap.is_empty() is True
heap = MaxHeap(capacity=10)
assert heap.is_empty() is True
heap.push(0)
assert heap.is_empty() is False
heap.pop()
assert heap.is_empty() is True
def test_size(self):
heap = MaxHeap()
assert heap.size == 0
heap = MaxHeap(capacity=10)
assert heap.size == 0
heap = MaxHeap([3, 2, 1])
assert heap.size == 3
heap.push(0)
assert heap.size == 4
heap.pop()
assert heap.size == 3
heap.pushpop(0)
assert heap.size == 3
heap.replace(0)
assert heap.size == 3
class RunningMedian:
def __init__(self):
self.left_max_heap = MaxHeap()
self.right_min_heap = MinHeap()
def stream_element(self, a):
left_len, right_len = self.left_max_heap.get_length(
), self.right_min_heap.get_length()
if left_len == right_len:
self.left_max_heap.push(a)
return
if left_len > right_len:
peek = self.left_max_heap.peek()
if a >= peek:
self.right_min_heap.push(a)
else:
popped = self.left_max_heap.pop()
self.left_max_heap.push(a)
self.right_min_heap.push(popped)
return
if left_len < right_len:
peek = self.right_min_heap.peek()
if a <= peek:
self.left_max_heap.push(a)
else:
popped = self.right_min_heap.pop()
self.right_min_heap.push(a)
self.left_max_heap.push(popped)
return
def get_current_median(self):
left_len, right_len = self.left_max_heap.get_length(
), self.right_min_heap.get_length()
if left_len == 0 and right_len == 0:
raise ("No element is streamed")
if left_len > right_len:
median = self.left_max_heap.peek()
return median
if right_len > left_len:
median = self.right_min_heap.peek()
return median
if left_len == right_len:
median = (self.left_max_heap.peek() +
self.right_min_heap.peek()) / 2.0
return median
def test_pop(self):
heap = MaxHeap()
with pytest.raises(EmptyError):
heap.pop()
heap.push(1)
assert heap.pop() == 1
heap.push(1)
heap.push(2)
heap.push(3)
assert heap.pop() == 3
heap = MaxHeap([1, 2, 3])
assert heap.pop() == 3
assert heap.pop() == 2
assert heap.pop() == 1
with pytest.raises(EmptyError):
heap.pop()
from max_heap import MaxHeap
my_heap = MaxHeap()
my_heap.heapify([8, 1, 5, 99, -12, 87])
print(f'my_heap init: {my_heap.heap}')
my_heap.push(200)
print(f'my_heap push: {my_heap.heap}')
pop_element = my_heap.pop()
print(f'my_heap pop: {my_heap.heap}, {pop_element}')
my_heap.heapify([1, 2, 3, 4, 5, 6, 7])
print(f'my_heap redefine: {my_heap.heap}')
