vector数组元素的排序

struct  student{    int sno;    int descore;    int caiscore;}stu;bool Sortarr( const student &a1, const student &a2){     return a1.descore > a2.descore;}int main(){    vector<student> v1;    for (int i = 0; i < 3; i++)    {        cin >> stu.sno >> stu.descore >> stu.caiscore;        v1.push_back(stu);//存入数组    }    sort(v1.begin(), v1.end(), Sortarr);//排序    //排序后    for (int i = 0; i<v1.size(); i++)    {        cout << v1[i].sno << " " << v1[i].descore << " " << v1[i].caiscore << endl;    }    return 0;}