vector sort AND 友元

# include<iostream>
# include<string>
# include<algorithm>
# include<stdio.h>
# include<vector>
using namespace std;
struct student
{
    int hao,h,w;
    string name;
}stu;
bool LessSort(student a,student b) { return (a.hao<b.hao); }
int main()
{
    int n,xh,xm,he,we;
    cin>>n;
    vector<student> v;
    for(int i=;i<n;i++)
    {
        cin>>stu.hao>>stu.name>>stu.h>>stu.w;
        v.push_back(stu);
    }
    sort(v.begin(),v.end(),LessSort);
    int count=,maxh,maxw,flag=;
    string maxname;
    for(int i=;i<n;i=i+)
    {
        if(i==)
        {
            maxh = v[i].h;
            maxname = v[i].name;
            maxw = v[i].w;
        }
        else
        {
            if(v[i].hao==v[i-].hao)
            {
                if(v[i].h>v[i-].h)
                {
                    maxh = v[i].h;
                    maxname = v[i].name;
                    maxw = v[i].w;
                }
            }
            else
            {
                printf("%06d ",v[i-].hao);
                cout<<maxname<<" "<<maxh<<" "<<maxw<<endl;
                maxh = v[i].h;
                maxname = v[i].name;
                maxw = v[i].w;
                if(i==n-)
                {
                    printf("%06d ",v[i-].hao);
                    cout<<maxname<<" "<<maxh<<" "<<maxw<<endl;
                }
            }
        }
    }
    return ;
}

#include<iostream>
using namespace std;
class Student
{
    public:
        Student()
        {
            number=;
            name;
            mark=;
        }
        void set_student();
        void show_student();
        friend void find(Student stu[],int q);
    private:
        int number;
        char name[];
        int mark;
};
void Student::set_student()
{
    cin>>number;
    cin>>name;
    cin>>mark;
}
void Student::show_student()
{
    cout<<number<<' '<<name<<' '<<mark<<endl;
}
void find(Student stu[],int q)
{
    int min=,w;
    for(int i=;i<q;i++)
    {
        if(stu[i].mark<min)
        {
            w=i;
            min=stu[i].mark;
        }
    }
    stu[w].show_student();
}
int main()
{
    int n;
    Student stu[];
    while(cin>>n)
    {
        if(n==)break;
        for(int i=;i<n;i++)
        {
            stu[i].set_student();
        }
        find(stu,n);
    }
    return ;
}