Heaps

Question 1

What is the purpose of heaps?

Answer 1

Heaps are used to find the min and max value in a set of values

Question 1

What Python package do you have to use to create a heap in Python?

Answer 1

heapq

Question 2

True or False: Python heaps can be either min heaps or max heaps

Answer 2

False - heaps are always min heaps in Python by default (can get around this by multiplying by -1)

Question 3

What is the syntax to add a value to a heap?

Answer 3

minHeap = [ ]
heaps.heappush(minHeap, n)

Question 4

How can we get the minimum value in a heap quickly in Python?

Answer 4

minHeap[0]

Question 5

How can we get the maximum value in a heap?

Answer 5

heapq.heappop(minHeap)

Question 6

How can we create a max heap in Python when Python only allows min heaps by default?

Answer 6

Can multiply the heap by -1

Question 7

What is the time complexity of building a heap in Python?

Answer 7

O(n) time (have to touch every value in an array)

heapq.heapify(arr)