Update heap_sort.c

Author: Shwetik

sorting/heap_sort.c

@@ -3,6 +3,7 @@
 void max_heapify(int *a, int i, int n);
 void heapsort(int *a, int n);
 void build_maxheap(int *a, int n);
+
 /**
  * max_heapify takes O(logn).
  */
@@ -40,6 +41,7 @@ void heapsort(int *a, int n)
         max_heapify(a, 1, i - 1);
     }
 }
+
 /**
  * build_maxheap takes O(n).
  */