给定一个可包含重复数字的整数集合 nums ，按任意顺序 返回它所有不重复的全排列。
示例 1：
输入：nums = [1,1,2]
输出：
[[1,1,2],
[1,2,1],
[2,1,1]]示例 2：
输入：nums = [1,2,3]
输出：[[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]提示：
1 <= nums.length <= 8-10 <= nums[i] <= 10
//leetcode submit region begin(Prohibit modification and deletion)
class Solution {
public List<List<Integer>> permuteUnique(int[] nums) {
Set<List<Integer>> result = new HashSet<>();
List<Integer> curRes = new ArrayList<>();
boolean[] chosen = new boolean[nums.length];
doPermute(result, curRes, chosen, nums);
return new ArrayList<>(result);
}
private void doPermute(Set<List<Integer>> result, List<Integer> curRes, boolean[] chosen, int[] nums) {
if (curRes.size() == nums.length) {
List<Integer> one = new ArrayList<>(curRes);
result.add(one);
return;
}
for (int i = 0; i < nums.length; i++) {
if (!chosen[i]) {
curRes.add(nums[i]);
chosen[i] = true;
doPermute(result, curRes, chosen, nums);
curRes.remove(curRes.size() - 1);
chosen[i] = false;
}
}
}
}
//leetcode submit region end(Prohibit modification and deletion)
