#include "stdafx.h"
#include <string>
#include <iostream>

using namespace std;

struct Student
{
	string faculNum;
	string name;
	int grades[4];
};

void enterData(Student studentData[], int &size_countStudents);
void average(Student studentData[], int size_countStudents);
void badGraders(Student studentData[], int size_countStudents);
void sortAndPrintExcelentStudents(Student studentData[], int size_countStudents);

void main()
{
	const int size_limit = 20;
	int size_countStudents = 0;
	Student studentData[size_limit];

	while (true)
	{
		int option;
		cout << "Press 1 for entering information about students." << endl;
		cout << "Press 2 for printing average for all students" << endl;
		cout << "Press 3 for printing badgraders" << endl;
		cout << "Press 4 for printring excellent students sorted alphabetically" << endl;
		cin >> option;

		switch (option)
		{
		case 1:
			enterData(studentData, size_countStudents);
			break;
		case 2:
			average(studentData, size_countStudents);
			break;
		case 3:
			badGraders(studentData, size_countStudents);
			break;
		case 4:
			sortAndPrintExcelentStudents(studentData, size_countStudents);
			break;

		default:
			cout << "Invalid input" << endl;
			break;
		}
	}
}

void enterData(Student studentData[], int &size_countStudents) //function for entering data about students
{
	cout << "Number of students:"; //enter number of students
	cin >> size_countStudents;  //change variable value to input

	for (int i = 0; i < size_countStudents; i++)
	{
		cout << "Enter data about student " << i + 1 << ":" << endl;

		cout << "Faculty number: ";
		cin >> studentData[i].faculNum;

		cout << "Name: ";
		cin >> studentData[i].name;

		cout << "Enter grades: ";
		cin >> studentData[i].grades[0];
		cin >> studentData[i].grades[1];
		cin >> studentData[i].grades[2];
		cin >> studentData[i].grades[3];
	}

	cout << studentData[0].name << studentData[0].grades[0] << studentData[0].grades[1] << studentData[0].grades[2] << studentData[0].grades[3] << endl;
}

void average(Student studentData[], int size_countStudents) //calc average for every student
{
	for (int i = 0; i < size_countStudents; i++)
	{
		//calculate average:
		double sum = studentData[i].grades[0] + studentData[i].grades[1] + studentData[i].grades[2] + studentData[i].grades[3];
		double average = sum / 4;

		//print:
		cout << studentData[i].faculNum << " " << studentData[i].name << " " << average << endl;
	}
}

void badGraders(Student studentData[], int size_countStudents) //print student with low grades
{
	for (int i = 0; i < size_countStudents; i++)
	{
		//calculate average:
		double sum = studentData[i].grades[0] + studentData[i].grades[1] + studentData[i].grades[2] + studentData[i].grades[3];
		double average = sum / 4;

		//print:
		if (average < 3) //bad grades students
		{
			cout << studentData[i].faculNum << " " << studentData[i].name << endl;
		}
	}
}

void sortAndPrintExcelentStudents(Student studentData[], int size_countStudents)
{
	//sort
	for (int h = 0; h < size_countStudents; h++)
	{
		for (int l = 0; l < size_countStudents - 1; l++)
		{
			if (studentData[l].name > studentData[l + 1].name)
			{
				//swap students
				Student temp = studentData[l];
				studentData[l] = studentData[l + 1];
				studentData[l + 1] = temp;
			}
		}
	}

	for (int i = 0; i < size_countStudents; i++)
	{
		//print:
		double sum = studentData[i].grades[0] + studentData[i].grades[1] + studentData[i].grades[2] + studentData[i].grades[3];
		double average = sum / 4;

		if (average >= 5.50) //excellent students
		{
			cout << studentData[i].faculNum << " " << studentData[i].name << endl;
		}
	}
}