Lintcode-medium-subsets

Given a set of distinct integers, return all possible subsets.

Notice

• Elements in a subset must is in non-descending order.
• The solution set must not contain duplicate subsets.

Example

If S = [1,2,3] , a solution is:

[  [3],  [1],  [2],  [1,2,3],  [1,3],  [2,3],  [1,2],  []]

Challenge

Can do it in both recursively and iteratively?

classSolution {/**     * @params:a set of numbers. * @return: A List of lists.     All valid subsets. */     Publicarraylist<arraylist<integer>> Subsets (int[] nums) {        //Write your code hereArrayList<ArrayList<Integer>> res =NewArraylist<arraylist<integer>>(); //Res.add (New arraylist<integer> ());ArrayList<Integer> line =NewArraylist<integer>();                Arrays.sort (Nums);  for(inti = 0; I <= nums.length; i++) {Helper (res, line, I,0, Nums); }                returnRes; }         Public voidHelper (arraylist<arraylist<integer>> Res, arraylist<integer> line,intLenintStartint[] nums) {                if(line.size () = =Len) {Res.add (NewArraylist<integer>(line)); return; }                 for(inti = start; i < nums.length; i++) {Line.add (nums[i]); Helper (res, line, Len, I+ 1, Nums); Line.remove (Line.size ()-1); }                return; }    }

Lintcode-medium-subsets