Array of Digits in a number sequence

Question

Well, I have a series of number from 1-999,999. Now I want to put every digit of those numbers in a separate array. I know, that really doesnt make any sense. this is what i mean:
for example i have number from 1-20
The the array will look like this
{1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 0, 1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1, 9, 2, 0}
therefore array[20]=5;
well, now I am trying to do this except, I am doing it with 1-999,999 instead of 20. I would really appreciate the help.
I already know that the size of the array that holds the separate digits from 1-999,999 is 5888889.
Here is what i have done:
public class NumberSeq
       public static void main (String[] args)
         int[] array= new long[5888889];
         for(int i=0;i<array.length;i++)
            for(int j=1;j<=999999;j++)
               String str = Integer.toString(j);
               if(j>9)
                  while(str.length()>0)
                     int num= Integer.parseInt(str.substring(0,1));
                     array=num;
str = str.substring(1,str.length());
i++;
array[i]=Integer.parseInt(str.substring(0,1));     
This is not my first attempt. I did many different attempts to make this work, but it always gave an exception.
Well the error is that, I am getting arrayindexoutofbounds exception. So :(. I would really appreciate any possible help.

Answer 1

Your problem was the use of that extra "i" loop rather than just incrementing the target array pointer as I have done. Try this:public class Test {
     public static void main(String[] args) {
          int[] array = new int[5888889];
          int i = 0;
          for (int j = 1; j <= 999999; j++) {
               String str = Integer.toString(j);
               while (str.length() > 0) {
                    int num = Integer.parseInt(str.substring(0, 1));
                    array[i++] = num;
                    str = str.substring(1);
}You were also unecessarily handling the last digit of each number by a special case, notice how I handle all the digits of each number the same way.
Regards,
Tim