class StringLooperTester {

  public static void main( String[] args ) {
    StringLooper looper = new StringLooper();
    System.out.println( "\nTest some okay (but contrived) ISBNs: " );
    checkExpect( looper.isValidISBN10("0000000000"), true  );
    checkExpect( looper.isValidISBN10("1000000001"), true  );
    checkExpect( looper.isValidISBN10("0100000002"), true  );
    checkExpect( looper.isValidISBN10("0010000003"), true  );
    checkExpect( looper.isValidISBN10("0001000004"), true  );
    checkExpect( looper.isValidISBN10("0000000019"), true  );
    checkExpect( looper.isValidISBN10("0000000027"), true  );
    checkExpect( looper.isValidISBN10("2000000010"), true  );
    checkExpect( looper.isValidISBN10("4000000020"), true  );
    checkExpect( looper.isValidISBN10("5000000080"), true  );
    System.out.println( "\nTest some real and incorrect ISBNs: " );
    checkExpect( looper.isValidISBN10("0306406152"), true  );
    checkExpect( looper.isValidISBN10("0306406162"), false );
    checkExpect( looper.isValidISBN10("0306406154"), false );
    checkExpect( looper.isValidISBN10("0553565699"), true  );
    checkExpect( looper.isValidISBN10("1553565699"), false );
    System.out.println( "\nTest some X-digit ISBNs: " );
    checkExpect( looper.isValidISBN10("000000000X"), false );
    checkExpect( looper.isValidISBN10("050000000X"), true  );
    checkExpect( looper.isValidISBN10("000020000X"), true  );
    checkExpect( looper.isValidISBN10("300000002X"), true  );
  }


  static void checkExpect( boolean actual, boolean expected ) {
    if (actual == expected) {
      System.out.print(".");
    }
    else {
      System.out.println("failed test: expected " + expected + ", got " + actual );
    }
  }

}