Create max_heap.py

heaps/max_heap.py

@@ -0,0 +1,82 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+class MaxHeap:
+    def __init__(self, heapsize):
+
+        self.heapsize = heapsize
+        self.maxheap = [0] * (heapsize + 1)
+        self.realsize = 0
+
+    def add(self, element):
+
+        self.realsize += 1
+        if self.realsize > self.heapsize:
+            print("Too many elements!")
+            self.realsize -= 1
+            return False
+
+        self.maxheap[self.realsize] = element
+        index = self.realsize
+        parent = index // 2
+
+        while self.maxheap[index] > self.maxheap[parent] and index > 1:
+            self.maxheap[parent], self.maxheap[index] = self.maxheap[index], self.maxheap[parent]
+            index = parent
+            parent = index // 2
+            
+    def peek(self):
+
+        return self.maxheap[1]
+    
+    def pop(self):
+
+        if self.realsize < 1:
+            print("Heap is empty.")
+            return False
+        else:
+            remove_element = self.maxheap[1]
+            self.maxheap[1] = self.maxheap[self.realsize]
+            self.realsize -= 1
+            index = 1
+
+            while (index <= self.realsize // 2):
+
+                left_children = index * 2
+                right_children = (index * 2) + 1
+
+                if (self.maxheap[index] < self.maxheap[left_children] or self.maxheap[index] < self.maxheap[right_children]):
+                    if self.maxheap[left_children] > self.maxheap[right_children]:
+                        self.maxheap[left_children], self.maxheap[index] = self.maxheap[index], self.maxheap[left_children]
+                        index = left_children
+                    else:
+                        self.maxheap[right_children], self.maxheap[index] = self.maxheap[index], self.maxheap[right_children]
+                        index = right_children
+                else:
+                    break
+            return remove_element
+    
+    def size(self):
+        return self.realsize
+    
+    def __str__(self):
+        return str(self.maxheap[1 : self.realsize + 1])
+        
+
+if __name__ == "__main__":
+
+        h = MaxHeap(5)
+        h.add(1)
+        h.add(2)
+        h.add(3)
+        print(h)
+
+        print(h.peek())
+        print(h.pop())
+        print(h.pop())
+        print(h.pop())
+        h.add(4)
+        h.add(5)
+        print(h)
+