Created C# implementation of HeapSort

sort/heap_sort/c-sharp/heapsort.cs

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+using System;
+
+namespace heapsort
+{
+    class HeapSort
+    {
+        static void Main(string[] args)
+        {
+            HeapSort heapsorter = new HeapSort();
+            //Unsorted array
+            int[] array = {1,14,10,9,3,6,2,8,5,7,16,4};
+
+            //Create a max heap
+            for (int i = array.Length / 2 - 1; i >= 0; i--) {
+                heapsorter.heapify(array, i, array.Length); 
+            }
+
+            //Sift down the heap
+            for (int i = array.Length - 1; i >= 0; i--) 
+            {
+                heapsorter.swap(array, 0, i);
+                heapsorter.heapify(array, 0, i); 
+            } 
+
+            //Output result
+            Console.Write("Sorted array: ");
+            foreach(var item in array) {
+                Console.Write(item.ToString() + " ");
+            }
+            Console.Write("\n");
+        }
+
+        //Create max heap from array
+        public void heapify(int[] heap, int start, int end) {
+            int left = 2 * start + 1;
+            int right = 2 * start + 2;
+
+            int largest = start;
+
+            //If the left node is larger than the current largest, it becomes the new largest
+            if (left < end && heap[left] > heap[largest]) {
+                largest = left;
+            }
+
+            //If the right node is larger than the current largest, it becomes the new largest
+            if (right < end && heap[right] > heap[largest]) {
+                largest = right;
+            } 
+
+            //If we haven't moved the largest element to the root node, keep going
+            if (largest != start) {
+                swap(heap, start, largest);
+                heapify(heap, largest, end);
+            }
+        }
+
+        //Swap two array elements
+        public void swap(int[] array, int x, int y) {
+            int temp = array[x];
+            array[x] = array[y];
+            array[y] = temp;
+        }
+    }
+}