Competitive/Collaborative Programming Class

import java.math.BigInteger;
import java.util.Scanner;

/*
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 * and open the template in the editor.
 */

/**
 *
 * @author ared38
 */
public class Main {
    
    BigInteger base=new BigInteger("26");
    Scanner cin=new Scanner(System.in);

    /**
     * @param args the command line arguments
     */
    void doIt(){
        //String s=cin.next();
        //BigInteger enc=encode(s);
        //System.out.println(formatEncoding(enc));
        //System.out.println(decode(enc));
        
        while(true){
            String word;
            String number;
            String input=cin.next();
            if(input.charAt(0)=='*'){
                break;
            }
            else if(Character.isDigit(input.charAt(0))){
                word=decode(new BigInteger(input));
                number=formatEncoding(new BigInteger(input));
            }
            else{
                word=input;
                number=formatEncoding(encode(input));
            }
            System.out.printf("%-22s%s\n",word,number);
        }
        
    }
    
    BigInteger encode(String word){
        BigInteger result=new BigInteger("0");
        for(char c:word.toCharArray()){
            result=result.multiply(base); //shift
            BigInteger charVal=new BigInteger(((Integer)(c-'a'+1)).toString());
            //System.out.println(c+"->"+charVal);
            result=result.add(charVal);
        }
        return result;
    }
    
    String decode(BigInteger coding){
        String result="";
        while(coding.compareTo(new BigInteger("0"))>0){
            int digit=coding.mod(base).intValue();
            coding=coding.divide(base);
            char cdigit=(char)('a'+digit-1);
            result=cdigit+result;
        }
        return result;
    }
    
    String formatEncoding(BigInteger coding){
        StringBuffer sb=new StringBuffer(coding.toString());
        for(int i=sb.length()-3;i>0;i-=3){
            sb.insert(i, ',');
        }
        return sb.toString();
    }
    
    public static void main(String[] args) {
        (new Main()).doIt();
    }
}

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