Qt 运算符重载 = 用于结构

无法为结构重载 = 运算符。程序可以编译，但在执行直接合并时会崩溃。

结构：

struct Student
    {
        QString fio;
        int group;
        int ysp[5];

        Student& operator = (const Student &s)
        {
            fio = s.fio;
            group = s.group;
            ysp[0] = s.ysp[0];
            ysp[1] = s.ysp[1];
            ysp[2] = s.ysp[2];
            ysp[3] = s.ysp[3];
            ysp[4] = s.ysp[4];
            ysp[5] = s.ysp[5];
            return (*this);
        }
    };

直接归并排序：

void MainWindow::Merge(Student *list_S, int left, int right)
{
    if (right == left) return;
    if (right - left == 1)
    {
        if (ui->Ascending->isChecked())
        {
            if (list_S[right].group < list_S[left].group) swap(list_S[right], list_S[left]);
        }
        if (ui->Descending->isChecked())
        {
            if (list_S[right].group > list_S[left].group) swap(list_S[right], list_S[left]);
        }
        return;
    }

    int m = (right + left) / 2;

    Merge(list_S,left, m);
    Merge(list_S,m + 1, right);

    Student buf[right];
    int xl = left;
    int xr = m + 1;
    int cur = 0;

    while (right - left + 1 != cur)
    {
        if (xl > m) buf[cur++] = list_S[xr++];
        else if (xr > right) buf[cur++] = list_S[xl++];

        else if (ui->Ascending->isChecked() && list_S[xl].group > list_S[xr].group)buf[cur++] = list_S[xr++];
        else if (ui->Descending->isChecked() && list_S[xl].group < list_S[xr].group)buf[cur++] = list_S[xr++];

        else buf[cur++] = list_S[xl++];

    }

    for (int i = 0; i < cur; i++) list_S[i + left] = buf[i];
}

如果在排序中更正，一切都会正常工作：

Student buf[right+1];