Initial data commit

Task/Sorting-algorithms-Heapsort/Picat/sorting-algorithms-heapsort.picat

@@ -0,0 +1,44 @@
+main =>
+  _ = random2(),
+  A = [random(-10,10) : _ in 1..30],
+  println(A),
+  heapSort(A),
+  println(A).
+
+heapSort(A) =>
+  heapify(A),
+  End = A.len,
+  while (End > 1)
+    swap(A, End, 1),
+    End := End - 1,
+    siftDown(A, 1, End)
+  end.
+
+heapify(A) =>
+  Count = A.len,
+  Start = Count // 2,
+  while (Start >= 1)
+    siftDown(A, Start, Count),
+    Start := Start - 1
+  end.
+
+siftDown(A, Start, End) =>
+  Root = Start,
+  Loop = true,
+  while (Root * 2 - 1 < End, Loop == true)
+    Child := Root * 2- 1,
+    if Child + 1 <= End, A[Child] @< A[Child+1] then
+      Child := Child + 1
+    end,
+    if A[Root] @< A[Child] then
+      swap(A,Root, Child),
+      Root := Child
+    else
+       Loop := false
+    end
+  end.
+
+swap(L,I,J)  =>
+  T = L[I],
+  L[I] := L[J],
+  L[J] := T.