/**
 * A utility class that implements the Soundex algorithm
 * for finding strings that sound the same
 *
 * @author  Prof. David Bernstein, James Madison University
 * @version 1.0
 */
public class Soundex
{

    /**
     * Construct a 4-character Soundex code from a String
     *
     * @param s   The String to convert
     * @return    The Soundex code
     */
    public static String toCode(String s)
    {
	char       c;
	char[]     code = {'0','0','0','0'};
	char[]     chars, coded, noDups, noHW, noVowels, source;
	int        i, index, n, start;


	// Create a character array
	chars = s.toUpperCase().toCharArray();


        // Remove non alphabetic characters
        source = new char[chars.length];        
        index = 0;
        for (i=0; i<chars.length; i++)
        {
           if ((chars[i] < 'A') || (chars[i] > 'Z'))
           {
              // Remove
           }
           else
           {
              source[index] = chars[i];
              index++;
           }
        }
        

	// Code the consonants
	coded = new char[index];
	for (i=0; i<coded.length; i++) {

	    c = source[i];
	    if       ((c=='B') || (c=='P') || (c=='F') || 
                      (c=='V')                            )   coded[i]='1';

	    else if  ((c=='C') || (c=='S') || (c=='K') || 
                      (c=='G') || (c=='J') || (c=='Q') || 
		      (c=='X') || (c=='Z')                )   coded[i]='2';

	    else if  ((c=='D') || (c=='T') )                  coded[i]='3';

	    else if  ((c=='L'))                               coded[i]='4';

	    else if  ((c=='M') || (c=='N') )                  coded[i]='5';

	    else if  ((c=='R'))                               coded[i]='6';
            else                                              coded[i]=c;
            
	}


        // Remove H and W  (except if the first letter)
        noHW    = new char[coded.length];
        noHW[0] = coded[0];
        index   = 1;
	for (i=1; i<coded.length; i++)
        {
	    if ((coded[i] == 'H') || (coded[i] == 'W'))
            {
               // Remove
            }
            else
            {
		noHW[index] = coded[i];
		index++;
	    }
	}
        

	// Remove duplicates
	noDups    = new char[index];
        noDups[0] = noHW[0];
        index     = 1;        
	for (i=1; i<noDups.length; i++)
        {
	    if (noHW[i] == noDups[index-1])
            {
		// Duplicate
	    }
            else
            {
		noDups[index] = noHW[i];
		index++;
	    }
	}


	// Remove the vowels (except if the first letter) and non-alphabetic
	noVowels    = new char[index];
	noVowels[0] = noDups[0];
	index       = 1;
	for (i=1; i<noVowels.length; i++) {

           if ((noDups[i]=='A') || (noDups[i]=='E') || (noDups[i]=='I') ||
               (noDups[i]=='O') || (noDups[i]=='U') || (noDups[i]=='Y')      )
            {
               // Remove
            }
            else
            {
		noVowels[index] = noDups[i];
		index++;
	    }
	}


	// Construct the final code
	code[0] = source[0];
	n = code.length;
	if (index < n) n = index;
	for (i=1; i<n; i++) code[i] = noVowels[i];




	return new String(code);
    }







}