Initial data commit

Task/Sorting-algorithms-Pancake-sort/VBA/sorting-algorithms-pancake-sort.vba

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+'pancake sort
+'uses two auxiliary routines "printarray" and "flip"
+
+Public Sub printarray(A)
+  For i = LBound(A) To UBound(A)
+    Debug.Print A(i),
+  Next
+  Debug.Print
+End Sub
+
+Public Sub Flip(ByRef A, p1, p2, trace)
+'flip first elements of A (p1 to p2)
+ If trace Then Debug.Print "we'll flip the first "; p2 - p1 + 1; "elements of the array"
+ Cut = Int((p2 - p1 + 1) / 2)
+ For i = 0 To Cut - 1
+   'flip position i and (n - i + 1)
+   temp = A(i)
+   A(i) = A(p2 - i)
+   A(p2 - i) = temp
+ Next
+End Sub
+
+Public Sub pancakesort(ByRef A(), Optional trace As Boolean = False)
+'sort A into ascending order using pancake sort
+
+lb = LBound(A)
+ub = UBound(A)
+Length = ub - lb + 1
+If Length <= 1 Then 'no need to sort
+  Exit Sub
+End If
+
+For i = ub To lb + 1 Step -1
+  'find position of max. element in subarray A(lowerbound to i)
+  P = lb
+  Maximum = A(P)
+  For j = lb + 1 To i
+    If A(j) > Maximum Then
+      P = j
+      Maximum = A(j)
+    End If
+  Next j
+  'check if maximum is already at end - then we don't need to flip
+  If P < i Then
+    'flip the first part of the array up to the maximum so it is at the head - skip if it is already there
+    If P > 1 Then
+      Flip A, lb, P, trace
+      If trace Then printarray A
+    End If
+    'now flip again so that it is in its final position
+    Flip A, lb, i, trace
+    If trace Then printarray A
+  End If
+Next i
+End Sub
+
+'test routine
+Public Sub TestPancake(Optional trace As Boolean = False)
+Dim A()
+A = Array(5, 7, 8, 3, 1, 10, 9, 23, 50, 0)
+Debug.Print "Initial array:"
+printarray A
+pancakesort A, trace
+Debug.Print "Final array:"
+printarray A
+End Sub