public static boolean sumNum(int[] a, int n)
    {
        return sumNum(a, n, 0, 0, 0,new int[a.length], new int[a.length], 0, 0);
    }
    private static boolean sumNum(int[] a, int n, int i, int s1, int s2, int[] hist1, int[] hist2, int ind1, int ind2)
    {
        if(i >= a.length)
        {
            if(s1 - s2 == n || s2 - s1 == n)
            {
                print(hist1, 0, ind1);
                System.out.println();
                print(hist2, 0, ind2);
                return true;
            }
            return false;
        }
        hist1[ind1] = a[i];
        if(sumNum(a, n, i+1, s1 + a[i], s2, hist1, hist2, ind1 + 1, ind2))
        {
            return true;
        }
        hist2[ind2] = a[i];
        return sumNum(a, n, i+1, s1, s2 + a[i], hist1, hist2, ind1, ind2 + 1);
    }
    private static void print(int[] a, int from, int to)
    {
        if(from < to)
        {
            System.out.print(a[from] + ", ");
            print(a, from+1, to);
        }
    }