check if the sudoku is valid or not .

public static boolean checkRow (int row, byte[1 [1 grid) ( return true; /**checks if column col' is OK in the grid/ public static boolean checkcolumn (int col, byte[] [ grid) return true; /**checks if the subregion 'region' is OK in the grid public static boolean checkSubregion (int region, byte[] grid) ( return true; public static boolean check (byte [] 1] grid) /7 check the subregions for (int subregion0: subregion