/* Import the Java I/O package */
import java.io.*;
import AppletConsoleApp;

/**
 * Solution to the 1998 British Informatics Olympiad exam
 * question 1: Roman numerals
 *
 * This application that can be run either from the console
 * as a stand-alone application or from an in-applet
 * console created with the AppletConsole applet.
 *
 * Solution copyright (c) 1998 The British Informatics Olympiad (BIO).
 *
 * This program may be freely copied by persons or organisations
 * involved in the British Informatics Olympiad or the International
 * Olympiad in Informatics, on condition that no changes are made and
 * this notice is not altered. Distribution for profit is forbidden
 * unless permission is first obtained in writing from the BIO.
 *
 * This program is for educational purposes only and comes with no
 * warranty, implied or otherwise, as to its fitness for any purpose.
 *
 * Author:   Antony Rix
 * Internet: http://www.christs.cam.ac.uk/bio/
 * E-mail:   a.rix@lineone.net
 * S-mail:   The British Informatics Olympiad
 *           Christ's College
 *           Cambridge CB2 3BU
 *           United Kingdom
 *
 * @author  Antony Rix
 * @version 0.1
 * @see     AppletConsoleApp
 * @see     AppletConsole
 */
class BIO98R1Q1App extends AppletConsoleApp {
  /**
   * Start the application from the command line.
   */
  public static void main(String[] args) {
	  BIO98R1Q1App thisApp = new BIO98R1Q1App();
	  thisApp.redirectStreams(System.in, System.out);
	  thisApp.run();
	}

  /**
   * The implementation of this application.
   * For 1(a), run() gets a number; if it is between 1 and
   * 3999 it translates it using toRoman(), and prints it.
   * If the number is less than 1, it solves part 1(c) by
   * exhaustive search.
   *
   * The answer to 1(b) is mccxlix + dcxv = mdccclxiv
   * (1249 + 615 = 1864).
   */
	public void run() {
    int n, i, lgth, countLess, countMore;

    out.println(
      "Enter a number from 1 to 3999:" );
    out.print( ">" );
    
    try {
  	  /* Create a StreamTokenizer to allow us to read in the two numbers
	    */
  	  StreamTokenizer sin = new StreamTokenizer( in );
	    sin.nextToken();
	    n = (int)sin.nval;
	    if( n <= 0 ) {
	      countLess = 0;
	      countMore = 0;
	      for( i = 1; i < 10; i++ ) {
	        lgth = toRoman( i ).length();
	        if( lgth > 1 ) countMore++;
	      }
	      for( i = 10; i < 100; i++ ) {
	        lgth = toRoman( i ).length();
	        if( lgth < 2 ) countLess++;
	        if( lgth > 2 ) countMore++;
	      }
	      for( i = 100; i < 1000; i++ ) {
	        lgth = toRoman( i ).length();
	        if( lgth < 3 ) countLess++;
	        if( lgth > 3 ) countMore++;
	      }
	      for( i = 1000; i < 4000; i++ ) {
	        lgth = toRoman( i ).length();
	        if( lgth < 4 ) countLess++;
	        if( lgth > 4 ) countMore++;
	      }
	      out.println( countLess + " Roman numerals from 1 to 3999 have fewer" );
	      out.println( "characters than digits and " + countMore + " have more." );
	    } else {
	      if( n < 4000 )
    	    out.println(
	          n + " -> " + toRoman( n ) + "." );
	      else
	        out.println( "Invalid number!" );
	    }
  	} catch (IOException e) { out.println("I/O failure"); };
	  out.println( "Program finished." );
	}

  static String[] units = // Units 0 to 9
    { "", "i", "ii", "iii", "iv", "v", "vi", "vii", "viii", "ix" };

  static String[] tens = // Tens 0 to 90
    { "", "x", "xx", "xxx", "xl", "l", "lx", "lxx", "lxxx", "xc" };
    
  static String[] hundreds = // Hundreds 0 to 900
    { "", "c", "cc", "ccc", "cd", "d", "dc", "dcc", "dccc", "cm" };

  static String[] thousands = // Thousands 0 to 3000
    { "", "m", "mm", "mmm" };

	public static String toRoman( int n ) {
	  return thousands[ (n / 1000) ] +
	         hundreds[ (n / 100) % 10 ] +
	         tens[ (n / 10) % 10 ] +
	         units[ (n) % 10 ];
	}
}