Why the last case [-1,2,0,-1,1,0,1] is wrong

```
class Solution {
public:
void backtrace(vector<int>& nums, int order, vector<vector<int>>& subs) {
if (order == nums.size()) {
subs.push_back(nums);
return;
}
int temp = INT_MIN;
for (int i = order; i < nums.size(); i++) {
if (i != order && nums[i] == nums[order]) {
continue;
}
if (temp == nums[i]) {
continue;
}
temp = nums[i];
swap(nums[order], nums[i]);
backtrace(nums, order + 1, subs);
swap(nums[order], nums[i]);
}
}
vector<vector<int>> permuteUnique(vector<int>& nums) {
vector<vector<int>> subs;
sort(nums.begin(), nums.end());
backtrace(nums, 0, subs);
return subs;
}
};
```