Initial data commit

Task/Sorting-algorithms-Shell-sort/FreeBASIC/sorting-algorithms-shell-sort.basic

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+' version 21-10-2016
+' compile with: fbc -s console
+' for boundry checks on array's compile with: fbc -s console -exx
+
+Sub shellsort(s() As Long)
+    ' sort from lower bound to the highter bound
+    ' array's can have subscript range from -2147483648 to +2147483647
+    Dim As Long lb = LBound(s)
+    Dim As Long ub = UBound(s)
+    Dim As Long done, i, inc = ub - lb
+
+    Do
+        inc = Int(inc / 2.2)
+        If inc < 1 Then inc = 1
+
+        Do
+            done = 0
+            For i = lb To ub - inc
+                ' replace "<" with ">" for downwards sort
+                If s(i) > s(i + inc) Then
+                    Swap s(i), s(i + inc)
+                    done = 1
+                End If
+            Next
+        Loop Until done = 0
+
+    Loop Until inc = 1
+
+End Sub
+
+' ------=< MAIN >=------
+
+Dim As Long i, array(-7 To 7)
+
+Dim As Long a = LBound(array), b = UBound(array)
+
+Randomize Timer
+For i = a To b : array(i) = i  : Next
+For i = a To b ' little shuffle
+    Swap array(i), array(Int(Rnd * (b - a +1)) + a)
+Next
+
+Print "unsorted ";
+For i = a To b : Print Using "####"; array(i); : Next : Print
+shellsort(array())  ' sort the array
+Print "  sorted ";
+For i = a To b : Print Using "####"; array(i); : Next : Print
+
+' empty keyboard buffer
+While InKey <> "" : Wend
+Print : Print "hit any key to end program"
+Sleep
+End