public static void main(String[] args) {
        int[] a = {1,2,2,3,4,5};
        TreeMap<String,String> tm = new TreeMap<String,String>();
        f(a,0,"",tm);
        Iterator<String> it = tm.keySet().iterator();
        while(it.hasNext()) {
            System.out.println(it.next());
        }
    }
    
    public static void f(int[] a,int n,String str,TreeMap<String,String> tm) {
        if(n==a.length-1) {
            String str_2 = str+a[n];
            if(!str_2.matches("\\d*?35\\d*?|\\d*?53\\d*?")&&!str_2.matches("[\\d]{2}4\\d+")) {
                tm.put(str_2, str_2);
            }
        }
        else {
            for(int i = n;i<a.length;i++) {
                int test = a[n];
                a[n] = a[i];
                a[i] = test;
                String str_2 = str+a[n];
                f(a,n+1,str_2,tm);
                a[i] = a[n];
                a[n] = test;
            }
        }
    }