Create heap.py

heaps/heap.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+class Heap:
+
+    def __init__(self):
+
+        self.heap = []
+
+    def heapify(self, n, i):
+
+        largest = i
+        left_children = 2 * i + 1
+        right_children = 2 * i + 2
+
+        if left_children < n and self.heap[i] < self.heap[left_children]:
+            largest = left_children
+
+        if right_children < n and self.heap[largest] < self.heap[right_children]:
+            largest = right_children
+
+        if largest != i:
+            self.heap[i], self.heap[largest] = self.heap[largest], self.heap[i]
+            self.heapify(n, largest)
+
+
+    def insert(self, num):
+
+        size = len(self.heap)
+
+        if size == 0:
+            self.heap.append(num)
+
+        else:
+            self.heap.append(num)
+            for i in range((size // 2) - 1, -1, -1):
+                self.heapify(size, i)
+
+
+    def delete_node(self, num):
+
+        size = len(self.heap)
+
+        i = 0
+        for i in range(size):
+            if num == self.heap[i]:
+                break
+
+        self.heap[i], self.heap[size - 1] = self.heap[size - 1], self.heap[i]
+
+        self.heap.remove(size - 1)
+
+        for i in range((len(self.heap) // 2) - 1, -1, -1):
+            self.heapify(len(self.heap), i)
+
+
+
+if __name__ == '__main__':
+
+    h = Heap()
+    for n in [10, 4, 9, 8, 1, 2]:
+        h.insert(n)
+
+    print (f'Max-heap array: {h.heap}')
+
+    n = 2
+    h.delete_node(n)
+    print(f'After deleting {n}: {h.heap}')