双色球--最多2个号码相同的内幕

虽然是标题党，但是功能却是能让双色球最多只有2个球号码相同，不知道没中过双色球或者只有2个双色球的小伙伴是不是买了假的双色球了啊。

代码如下：
class Doubleball{
public static void main(String[] args){
            String pool[]={"01","02","03","04","05","06"
         ,"07","08","09","10","11","12","13","14",
        "15","16","17","18","19","20","21","22",
        "23","24","25","26","27","28","29","30",
        "31","32","33"};
                Random rad=new Random();
                String str=new String[6];
                int index=0;
                int i=0
                boolean used[]=new boolean[pool.length];
                while (index

used数组已经将前6个中相同的跳过了，因此最多只能出现一个号码相同最终。