How can I write a function that can accept a binary tree as a parameter and returns True if it is a min heap and False if not.
from heapq import heapify
def binary_heap(tree):
while len(tree) > 1:
if heapify(tree):
return True
else:
return False
Since a min heap has to satisfy, per heapq's documentation:
heap[k] <= heap[2*k+1] and heap[k] <= heap[2*k+2]
You can iterate through all child nodes to validate that they are greater than or equal to their parent nodes (note that i - 1 >> 1 is a shorthand for (i - 1) // 2 when i > 0):
def is_minheap(lst):
return all(lst[i] >= lst[i - 1 >> 1] for i in range(1, len(lst)))
so that:
from heapq import heapify
from random import sample
lst = sample(range(10), 10)
print(is_minheap(lst), lst)
heapify(lst)
print(is_minheap(lst), lst)
outputs something like:
False [1, 2, 6, 8, 0, 5, 3, 9, 7, 4]
True [0, 1, 3, 7, 2, 5, 6, 9, 8, 4]