CODE EXAMPLE FOR PYTHON

python implementation of Min Heap

# Python3 implementation of Min Heap
 
import sys
 
class MinHeap:
 
    def __init__(self, maxsize):
        self.maxsize = maxsize
        self.size = 0
        self.Heap = [0]*(self.maxsize + 1)
        self.Heap[0] = -1 * sys.maxsize
        self.FRONT = 1
 
    # Function to return the position of
    # parent for the node currently
    # at pos
    def parent(self, pos):
        return pos//2
 
    # Function to return the position of
    # the left child for the node currently
    # at pos
    def leftChild(self, pos):
        return 2 * pos
 
    # Function to return the position of
    # the right child for the node currently
    # at pos
    def rightChild(self, pos):
        return (2 * pos) + 1
 
    # Function that returns true if the passed
    # node is a leaf node
    def isLeaf(self, pos):
        return pos*2 > self.size
 
    # Function to swap two nodes of the heap
    def swap(self, fpos, spos):
        self.Heap[fpos], self.Heap[spos] = self.Heap[spos], self.Heap[fpos]
 
    # Function to heapify the node at pos
    def minHeapify(self, pos):
 
        # If the node is a non-leaf node and greater
        # than any of its child
        if not self.isLeaf(pos):
            if (self.Heap[pos] > self.Heap[self.leftChild(pos)] or
               self.Heap[pos] > self.Heap[self.rightChild(pos)]):
 
                # Swap with the left child and heapify
                # the left child
                if self.Heap[self.leftChild(pos)] < self.Heap[self.rightChild(pos)]:
                    self.swap(pos, self.leftChild(pos))
                    self.minHeapify(self.leftChild(pos))
 
                # Swap with the right child and heapify
                # the right child
                else:
                    self.swap(pos, self.rightChild(pos))
                    self.minHeapify(self.rightChild(pos))
 
    # Function to insert a node into the heap
    def insert(self, element):
        if self.size >= self.maxsize :
            return
        self.size+= 1
        self.Heap[self.size] = element
 
        current = self.size
 
        while self.Heap[current] < self.Heap[self.parent(current)]:
            self.swap(current, self.parent(current))
            current = self.parent(current)
 
    # Function to print the contents of the heap
    def Print(self):
        for i in range(1, (self.size//2)+1):
            print(" PARENT : "+ str(self.Heap[i])+" LEFT CHILD : "+
                                str(self.Heap[2 * i])+" RIGHT CHILD : "+
                                str(self.Heap[2 * i + 1]))
 
    # Function to build the min heap using
    # the minHeapify function
    def minHeap(self):
 
        for pos in range(self.size//2, 0, -1):
            self.minHeapify(pos)
 
    # Function to remove and return the minimum
    # element from the heap
    def remove(self):
 
        popped = self.Heap[self.FRONT]
        self.Heap[self.FRONT] = self.Heap[self.size]
        self.size-= 1
        self.minHeapify(self.FRONT)
        return popped
 
# Driver Code
if __name__ == "__main__":
     
    print('The minHeap is ')
    minHeap = MinHeap(15)
    minHeap.insert(5)
    minHeap.insert(3)
    minHeap.insert(17)
    minHeap.insert(10)
    minHeap.insert(84)
    minHeap.insert(19)
    minHeap.insert(6)
    minHeap.insert(22)
    minHeap.insert(9)
    minHeap.minHeap()
 
    minHeap.Print()
    print("The Min val is " + str(minHeap.remove()))