Data update

Task/Random-Latin-squares/FreeBASIC/random-latin-squares.basic

@@ -0,0 +1,75 @@
+Randomize Timer
+
+Sub printSquare(latin() As Integer, n As Integer)
+    For i As Integer = 0 To n - 1
+        Print "[";
+        For j As Integer = 0 To n - 1
+            Print latin(i, j); ",";
+        Next j
+        Print Chr(8); " ]"
+    Next i
+    Print
+End Sub
+
+Sub latinSquare(n As Integer)
+    Dim As Integer i, j, k
+
+    If n <= 0 Then
+        Print "[]"
+        Exit Sub
+    End If
+    Dim latin(n - 1, n - 1) As Integer
+    For i = 0 To n - 1
+        For j = 0 To n - 1
+            latin(i, j) = j
+        Next j
+    Next i
+
+    ' first row
+    For i = 0 To n - 1
+        Dim j As Integer = Int(Rnd * n)
+        Swap latin(0, i), latin(0, j)
+    Next i
+
+    ' middle row(s)
+    For i = 1 To n - 2
+        Dim shuffled As Integer = 0
+        While shuffled = 0
+            For j = 0 To n - 1
+                Dim k As Integer = Int(Rnd * n)
+                Swap latin(i, j), latin(i, k)
+            Next j
+            shuffled = 1
+            For k As Integer = 0 To i - 1
+                For j = 0 To n - 1
+                    If latin(k, j) = latin(i, j) Then
+                        shuffled = 0
+                        Exit For
+                    End If
+                Next j
+                If shuffled = 0 Then Exit For
+            Next k
+        Wend
+    Next i
+
+    ' last row
+    For j = 0 To n - 1
+        Dim used(n - 1) As Integer
+        For i = 0 To n - 2
+            used(latin(i, j)) = 1
+        Next i
+        For k = 0 To n - 1
+            If used(k) = 0 Then
+                latin(n - 1, j) = k
+                Exit For
+            End If
+        Next k
+    Next j
+    printSquare(latin(), n)
+End Sub
+
+latinSquare(5)
+latinSquare(5)
+latinSquare(10) ' for good measure
+
+Sleep