题解 | #有重复项数字的全排列#

class Solution {
  public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param num int整型vector
     * @return int整型vector<vector<>>
     */
    vector<vector<int>> res;
    void pailie(vector<int>& num, int n, int k, vector<int>& path,
                vector<bool>& mark) {
        if (k == n) {
            res.push_back(path);
            return;
        }
        for (int i = 0; i < n; i++) {
            if (!mark[i]) {
                path.push_back(num[i]);
                mark[i] = true;
                pailie(num, n, k + 1, path, mark);
                path.pop_back();
                mark[i] = false;
            }
        }
    }
    vector<vector<int> > permuteUnique(vector<int>& num) {
        vector<bool> mark(num.size(), false);
        vector<int> path;
        pailie(num, num.size(), 0, path, mark);
        sort(res.begin(),res.end());
        res.erase(unique(res.begin(),res.end()),res.end());
        return res;
    }
};