Added Heap Sort algorithm

HeapSort.java

@@ -0,0 +1,65 @@
+public class HeapSort {
+
+	    public void heapSort(int arr[])
+	    {
+	        int temp;
+
+	        for (int i = arr.length / 2 - 1; i >= 0; i--)               
+	        {
+	            heapify(arr, arr.length, i);
+	        }
+
+	        for (int i = arr.length - 1; i > 0; i--)                          
+	        {
+	            temp = arr[0];                                                 
+	            arr[0] = arr[i];
+	            arr[i] = temp;
+	            heapify(arr, i, 0);                                            
+	        }
+	    }
+
+	    void heapify(int arr[], int n, int i)
+	    {
+	        int MAX = i; 
+	        int left = 2 * i + 1; 
+	        int right = 2 * i + 2; 
+	        int temp;
+
+	        if (left < n && arr[left] > arr[MAX])            
+	        {
+	            MAX = left;
+	        }
+
+	        if (right < n && arr[right] > arr[MAX])           
+	        {
+	            MAX = right;
+	        }
+
+	        if (MAX != i) 
+	        {                                              
+	            temp = arr[i];
+	            arr[i] = arr[MAX];
+	            arr[MAX] = temp;
+	            heapify(arr, n, MAX);
+	        }
+	    }
+
+	    void display(int arr[])             //view array
+	    {  
+	        for (int i=0; i<arr.length; ++i) 
+	        {
+	            System.out.print(arr[i]+" ");
+	        } 
+	    } 
+
+	    public static void main(String args[])
+	    {
+	        int arr[] = { 4, 15, 6 , 2, 11, 25, 10 };
+
+	        HeapSort ob = new HeapSort();
+	        ob.heapSort(arr);
+	        ob.display(arr);
+	    }
+
+
+}