1. Array-Based Heap

class Heaps:
    def __init__(self):
        self.data = []
    
    def root_node(self):
        return self.data[0]

    def last_node(self):
        return self.data[-1]

2. Traversing an Array-Based Heap

2.1 Child of Any Node

To find the child of any node in an array-based heap, the following formula is always True:

left_child:

(index*2)+1

right_child:

(index*2)+2

2.2 Child of Any Node: Code

def left_child_index(self, index):
    return (index*2)+1

def right_child_index(self, index):
    return (index*2)+2

2.3 Parent of Any Node

Any node’s parent:

(index-1)//2 (Note // is floor division)

def parent_index(self, index):
    return (index-1)//2

3. Insertion

def insert(self, value):
    self.data.append(value)
    new_node_index = len(self.data)-1
    
    while(new_node_index>0 and 
          (self.data[new_node_index] > self.data[self.parent_index(new_node_index)])):
        parent_index = self.parent_index(new_node_index)
        self.data[parent_index], self.data[new_node_index] = self.data[new_node_index], self.data[parent_index]
        
        new_node_index=parent_index