Что не так с деструктором?

#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<vector>
#include <iomanip>
#include <algorithm>
using namespace std;
class student
{
 
    char *name;
    char*surname;
    int curs;
public:
    student()
    {
        name = new char[50];
        surname = new char[50];
        curs = 0;
    }
    student( char *nm,char *srn,int cr)
    {
        name = new char[50];
        surname = new char[50];
        strncpy(name, nm,strlen(nm));
        strncpy(surname, srn,strlen(srn));
        curs = cr;
    }
    ~student()
    {
        delete[]name;
        delete[]surname;
    }
    friend ostream& operator <<(ostream &out,const student &a)
    {
        out << a.name << "  " << a.surname << " " << a.curs << endl;
        return out;
    }
    friend istream& operator >>(istream &in, student &a)
    {
        in >> a.name;  
        in >> a.surname; 
        in >> a.curs;
        return in;
    }
    void vectorfill(vector<student>&stud)
    {
        char *ask = new char[3];
        while (true)
        {
 
            student students;
            cin >> students;
            cout << students;
            stud.push_back(student(name, surname, curs));
            cin >> ask;
            if (strcmp(ask, "no") == 0)
                break;
        }
        delete[]ask;
    }
};
int main()
{
    vector<student>stud;
    student a;
    a.vectorfill(stud);
    system("pause");
    return 0;
}

#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<vector>
#include <iomanip>
#include <algorithm>
using namespace std;
class student
{
public:
    char *name;
    char*surname;
    int curs;
    student()
    {
        name = new char[50];
        surname = new char[50];
        curs = 0;
    }
    student( char *nm,char *srn,int cr)
    {
        name = new char[50];
        surname = new char[50];
        strncpy(name, nm,strlen(nm));
        strncpy(surname, srn,strlen(srn));
        curs = cr;
    }
    friend ostream& operator <<(ostream &out,const student &a)
    {
        out << a.name << "  " << a.surname << " " << a.curs << endl;
        return out;
    }
    friend istream& operator >>(istream &in, student &a)
    {
        cout << "name: ";
        in >> a.name; 
        cout << "surname: ";
        in >> a.surname; 
        cout << "curse: ";
        in >> a.curs;
        return in;
    }
    
};
void vectorfill(vector<student> &stud)
{
    char *ask = new char[3];
    student students;
    while (true)
    {
 
        cin >> students;
        stud.push_back(student(students.name, students.surname, students.curs));
        cin >> ask;
        if (strcmp(ask, "no") == 0)
            break;
    }
}
void show_vector(vector<student> &stud)
{
    cout << stud.size();
    vector<student>::iterator show;
    for (show = stud.begin(); show <stud.end(); show++)
        cout << *show << endl;
}
void main()
{
    vector<student> stud;
    student a;
    vectorfill(stud);
    show_vector(stud);
    system("pause");
    
}