Given a collection of numbers that might contain duplicates, return all possible unique permutations.
Example:
Input: [1,1,2] Output: [ [1,1,2], [1,2,1], [2,1,1] ]
class Solution {
public:
vector<vector<int>> permuteUnique(vector<int>& nums) {
sort(nums.begin(),nums.end());
vector<vector<int>>result;
vector<int>temp;
do{
if(temp!=nums)
result.push_back(nums);
temp=nums;
}while(next_permutation(nums.begin(),nums.end()));
return result;
}
};