New to Java

Hi,

I am trying to make a program that generates n-bit Gray code. The reflected binary code, also known as Gray code, is a binary numeral system where two successive values differ in only one bit.

Another explanation would be - an n-bit Gray code is a list of the 2^n different n-bit binary numbers such that each entry in the list differs in precisely one bit from its predecessor.

If I want to generate 1-bit gray code that would be:

*0*
*1*

2-bits would be:

*0 0*
*0 1*
*1 1*
*1 0*


3-bits would be:

*0 0 0*
*0 0 1*
*0 1 1*
*0 1 0*
*1 1 0*
*1 1 1*
*1 0 1*
*1 0 0*

and so on.


This is what I have so far:

public class GrayCode {

	static void genGC(int n){
		
		if(n == 0){
			System.out.println(n);
		}
		else{
			genGC(n-1);
			
			genGC(n-1);
		}
		
	}
	
	public static void main(String[] args) {
		
		int a = 1;
		
		genGC(a);

	}

}

So, in the case of 1-bit gray code the above program would output:

*0*
*0*

for 2-bits code:

*0*
*0*
*0*
*0*

etc.

Any ideas or hints what to do in order to go further are greatly appreciated.
Thanks in advance.