PROGRAM PROG12A;
{$U+    Copyright (C), 1985 by Lyle Faurot.  All rights reserved.

    New Topics:  Writing your own function

}

VAR
  No : Integer;

FUNCTION Has_Valid_Cube(Number:Integer) : Boolean;

BEGIN
  If (Number < -32) OR (Number > 31)
    THEN
      Has_Valid_Cube := False
    ELSE
      Has_Valid_Cube := True;
END;

FUNCTION Cube(Number:Integer) : Integer;

BEGIN
  Cube := Number * Number * Number;
END;


BEGIN
  Write('Enter a number: ');
  ReadLn(No);
  If Has_Valid_Cube (No)
    THEN
      WriteLn('The cube is: ', Cube(No) )
    ELSE
      BEGIN
        WriteLn('The cube of ',No,' is outside the integer range');
        WriteLn('in this version of Pascal.');
      END;
END.