Subsets Ii--leetcode

Given a collection of integers that might contain duplicates, Nums, return all possible subsets.

Note:

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

For example,
If nums = [1,2,2] , a solution is:

[  2],  [1],  [1,2,2],  [2,2], [up  ],  []]

Given an array, return all possible subcollections, the array has repeating elements, but the subcollections cannot be duplicated.

Problem-solving ideas: This problem I first sort, and then traverse, the current element is not a duplicate of the element will be in the res all the list is removed and the current element is added to the res, is a repeating element of the last addition to the Res list of this element, and then add a repeating element to the Res.

     PublicList<list<integer>> Subsetswithdup (int[] nums) {List<List<Integer>> res =NewArraylist<>(); if(Nums = =NULL|| Nums.length = = 0) {            returnRes;        } arrays.sort (Nums); Res.add (NewArraylist<integer>()); intLastsize = 0, Currsize;  for(inti = 0; i < nums.length; i++) {            intStart = (i > 0 && nums[i] = = Nums[i-1])? lastsize:0; Currsize=res.size ();  for(intj = start; J < Currsize; J + +) {List<Integer> tmp =NewArraylist<>(Res.get (j));                Tmp.add (Nums[i]);            Res.add (TMP); } lastsize=currsize; }        returnRes; }

Subsets Ii--leetcode