C++ mem_fun

#include <stdio.h>
#include <string>
#include <iostream>
#include <fstream>
#include <iterator>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;


class Student
{
private:
    int sno;
public:
    Student(int i)
    {
        sno=i;
    }
    int getSno()
    {
        return sno;
    }
    void printSno()
    {
        cout<<sno<<endl;
    }
    
};
vector<Student*> student_p;;
void insertStudent(int& sno)
{
    Student*sp=new Student(sno);
    student_p.push_back(sp);
}

int  main()
{
    
    ifstream is("1");

    istream_iterator<int> ii(is);
    istream_iterator<int> eos;

    vector<int> v(ii,eos);

    for_each(v.begin(),v.end(),insertStudent);
    for_each(student_p.begin(),student_p.end(),mem_fun(&Student::printSno));

    return 0;
}