g5-04180. GESP-5级-2023-12-单选-第07题 未做

下面的 C++ 代码实现对 list 的快速排序，有关说法，错误的是（ ）。

vector<int> operator + (vector<int>lA, vector<int>lB)
{
    vector<int>lst;

    for (int i = 1; i < lA.size(); i++)
        lst.push_back(lA[i]);
    for (int i = 1; i < lB.size(); i++)
        lst.push_back(lB[i]);

    return lst;
}
vector<int> qSort(vector<int>lst)
{
    if (lst.size() < 2)
        return lst;
    int pivot = lst[0];
    vector<int> less, greater;
    for (int i = 1; i < lst.size(); i++)
        if (lst[i] <= pivot) less.push_back(lst[i]);
        else greater.push_back(lst[i]);
    for (int i = 1; i < lst.size(); i++)
        if (lst[i] <= pivot) less.push_back(lst[i]);
        else greater.push_back(lst[i]);

    return ____________;
}

• A. qSort(less) + qSort(greater) + (vector<int>)pivot
• B. (vector<int>)pivot + (qSort(less) + qSort(greater))
• C. (qSort(less) + (vector<int>)pivot + qSort(greater))
• D. qSort(less) + pivot + qSort(greater)