September Morn Update

Task/Sorting-algorithms-Heapsort/Julia/sorting-algorithms-heapsort.julia

@@ -0,0 +1,23 @@
+swapa(a, i, j) = begin a[i], a[j] = a[j], a[i] end
+
+function pd!(a, first, last)
+    while (c = 2 * first - 1) < last
+        if c < last && a[c] < a[c + 1]
+            c += 1
+        end
+        if a[first] < a[c]
+            swapa(a, c, first)
+            first = c
+        else
+            break
+        end
+    end
+end
+
+hfy!(a, n) = (f = div(n, 2); while f >= 1 pd!(a, f, n); f -= 1 end)
+
+heapsort!(a) = (n = length(a); hfy!(a, n); l = n; while l > 1 swapa(a, 1, l); l -= 1; pd!(a, 1, l) end; a)
+
+a = shuffle(collect(1:12))
+println("Unsorted: $a")
+println("Heap sorted: ", heapsort!(a))