78. Subsets

    public static List<List<Integer>> subsets(int[] nums) {        List<List<Integer>> list = new ArrayList<>();        for(int i = 1; i <= nums.length; i++) {            List<List<Integer>> tlist = recurSub(nums, 0, i);            for(List<Integer> tmp: tlist) {                list.add(tmp);            }        }        list.add(new ArrayList<>());        return list;    }    public static List<List<Integer>> recurSub(int[] nums, int start,int len) {        List<List<Integer>> list = new ArrayList<>();        for(int i = start; i < nums.length; i++) {            if(len > 1) {                for(List<Integer> tList : recurSub(nums, i+1, len-1)) {                    tList.add(nums[i]);                    list.add(tList);                }            }else if(len == 1) {                 list.add(new LinkedList<Integer>(Arrays.asList(nums[i])));            }        }        return list;    }