re: combinations of 4

[KF <dotslash () snosoft com>]

Heres a piece of java code from Peacenuker (www.skreel.org <http://www.skreel.org> 's admin). This helped me realise why doing this in java made my head hurt. 
Thanks again everyone .. I certainly did not expect a response from half the planet!
-KF

import java.io.*;

public class Combinaison
{

        private static String   [] tableChar_dec        = {"ABCDZ", "ABCDZ", "ABCDZ","ABCDZ"};
        private static int              [] currentIdx_dec       = {0, 0, 0, 0};


        public static void getCombination(String [] tableChar, int [] currentIdx)
        {
                if(currentIdx.length != tableChar.length)
                        throw new IllegalArgumentException("The supplied arrays don't have the same size !");

                if(isFinished(tableChar, currentIdx))
                        return;

                System.out.println(getCombinaison(tableChar, currentIdx));

                do
                {
                        incrementIdx(tableChar, currentIdx);
                        System.out.println(getCombinaison(tableChar, currentIdx));
                }
                while(!isFinished(tableChar, currentIdx));
        }


        //Look for the index to increment (from the end of the array)
        private static boolean incrementIdx(String [] tableChar, int [] currentIdx)
        {
                for(int i=tableChar.length - 1;i>= 0; i--)
                {
                        if(tableChar[i].length() > (currentIdx[i]+1))
                        {
                                currentIdx[i]++;
                                return true;
                        }
                        else
                                currentIdx[i]=0;
                }
                return false;//Argh, all is 0, now !!! returned to the beginning ;)
        }

        //Are all index to the size of the string ?
        private static String getCombinaison(String [] tableChar, int [] currentIdx)
        {
                StringBuffer foobar=new StringBuffer(tableChar.length);//initial capacity will avoid more than one alloc
                for(int i=0;i< tableChar.length;i++)
                {
                        foobar.append(tableChar[i].charAt(currentIdx[i]));
                }
                return foobar.toString();
        }

        //Are all index to the size of the string ?
        private static boolean isFinished(String [] tableChar, int [] currentIdx)
        {
                for(int i=0;i< tableChar.length;i++)
                {
                        if(tableChar[i].length() != (currentIdx[i]+1))
                                return false;
                }
                return true;
        }

        public static void main(String args[])
        {
                try
                {
                        Combinaison.getCombination(tableChar_dec, currentIdx_dec);
                }
                catch(Exception e)
                {
                        System.err.println("ERROR when generating combination");
                }
        }
}