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Task/Mutual-recursion/FreeBASIC/mutual-recursion.freebasic

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+' FB 1.05.0 Win64
+
+' Need forward declaration of M as it's used
+' by F before its defined
+Declare Function M(n As Integer) As Integer
+
+Function F(n As Integer) As Integer
+   If n = 0 Then
+     Return 1
+   End If
+   Return n - M(F(n - 1))
+End Function
+
+Function M(n As Integer) As Integer
+   If n = 0 Then
+     Return 0
+   End If
+   Return n - F(M(n - 1))
+End Function
+
+Dim As Integer n = 24
+Print "n :";
+For i As Integer = 0 to n : Print Using "###"; i;    : Next
+Print
+Print String(78, "-")
+Print "F :";
+For i As Integer = 0 To n : Print Using "###"; F(i); : Next
+Print
+Print "M :";
+For i As Integer = 0 To n : Print Using "###"; M(i); : Next
+Print
+Print "Press any key to quit"
+Sleep