#include <iostream>
#include <map>
#include <string>

using namespace std;

class Student {
friend ostream &operator<<(ostream&, const Student);
public:
	string name;
	int age;
	float grade;
};

ostream &operator<<(ostream& output, const Student s)
{
	output << s.name << "\t" << s.age << "\t" << s.grade;
	return output;
}

// typedef multimap<int, Student> ClassRoll;
typedef map<int, Student> ClassRoll;

void InsertStudent(int id, string name, int age, 
				   float grade, ClassRoll& c)
{
	Student s;

	s.age = age;
	s.grade = grade;
	s.name = name;

	c[id] = s;

//	c.insert(ClassRoll::value_type(id, s));
}

void PrintMap(ClassRoll c)
{
	ClassRoll::const_iterator i;

	cout << "Class roll: " << endl << endl;
	cout << "ID" << "\t\t" << "Name" << "\t\t" << "Age" << 
		    "\t" << "Grade" << endl;
	cout << "----------------------------------------------" << endl;

	for (i=c.begin(); i != c.end(); i++) 
		cout << i->first << "\t" << i->second << endl;

	cout << endl;
}

void CurveGrades(ClassRoll& c, float diff)
{
	ClassRoll::iterator i;

	for (i=c.begin(); i != c.end(); i++) 
		i->second.grade += diff;	
}

void main (void)
{
	ClassRoll students;
//	Student s;

	InsertStudent(123456789, "Jon Preston", 43, 99.6f, students);
	InsertStudent(123456789, "Jon Preston", 43, 99.6f, students);
	InsertStudent(777777777, "Alice Walker", 13, 79.2f, students);
	InsertStudent(234567655, "Bob Smith", 44, 100.2f, students);
	PrintMap(students);

	CurveGrades(students, 10.0f);

	PrintMap(students);
}