import java.io.*;

/**
 * This application displays the sum of the integers in a specified
 * range.
 *
 * @author  author name
 * @version  1.0.0
 */
public class SumCalculator  {

	private static BufferedReader  stdIn =
		new BufferedReader(new  InputStreamReader(System.in));

	private static PrintWriter  stdOut =
		new PrintWriter(System.out, true);

	private static PrintWriter  stdErr =
		new PrintWriter(System.err, true);

	/**
	 * Returns the sum of the integers in the specified
	 * range [lower,upper].
	 *
	 * @param lower  the lower limit.
	 * @param upper  the upper limit.
	 * @return  the sum of the integers in the specified
	 *          range [lower,upper].
	 */
	public static int  sumRange(int lower, int upper)  {

		stdErr.println("  sumRange called.  lower:" + lower
			+ "  upper:"  + upper);

		int  total = 0;

		for (int i = lower ; i <= upper; i++) {
			total += i;
			stdErr.println("    for loop,  i:" + i + "  total:"
				+ total);
		}

		return total;
	}

	/**
	 * Displays the sum of the integers in a specified range.
	 *
	 * @param args  not used.
	 */
	public static void  main(String[] args)  {

		int lower;
		int upper;

		try  {
			stdErr.print("lower limit:  ");
			stdErr.flush();
			lower = Integer.parseInt(stdIn.readLine());
			stdErr.print("upper limit:  ");
			stdErr.flush();
			upper = Integer.parseInt(stdIn.readLine());
			stdOut.println("The result is: " + sumRange(lower, upper));
		} catch (NumberFormatException  nfe)  {
			stdErr.println(nfe);
		} catch (IOException  ioe)  {
			stdErr.println(ioe);
		}

	}
}

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