标签：
Given a collection of integers that might contain duplicates, nums, return all possible subsets.
Note: 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], [1,2], [] ]
class Solution {
public:
vector<vector<int>> res;
vector<vector<int>> subsetsWithDup(vector<int>& nums) {
sort(nums.begin(),nums.end());
vector<int> t;
DFS(nums,t,0);
sort(res.begin(),res.end());
vector<vector<int>>::iterator it=unique(res.begin(),res.end()); //unique把重复的都扔掉后面，it指向的是所有不重复元素后的第一个位置
res.erase(it,res.end()); //删除it后的所有元素
return res;
}
void DFS(vector<int>& nums,vector<int>& cur,int k)
{
if(cur.size()==nums.size())
{
res.push_back(cur);
return;
}
else
{
res.push_back(cur);
for(int i=k;i<nums.size();i++)
{
vector<int> tmp=cur;
tmp.push_back(nums[i]);
DFS(nums,tmp,i+1);
}
}
}
};标签：
原文地址：http://blog.csdn.net/u011391629/article/details/52152199
