Prototype code

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

void PrintEmails();
void SelectTeachers();

string Teachers[100];

int main () 
{
	string line;
	int count = 0;
	ifstream myfile ("Teachers.txt");

	if (myfile.is_open())
	{
		while ( getline (myfile,line) )
		{
			Teachers[count] = line;
			count++;
		}
			myfile.close();
	}

	else cout << "Unable to open file"; 
	PrintEmails();
	SelectTeachers();
}

void PrintEmails()
{
	int count = 1;
	while(Teachers[count - 1] != "\0")
	{
		cout << count << ": " << Teachers[count - 1];
		if(count % 3 == 0)
		{
			cout << endl;
		}
		else
		{
			cout << "\t";
		}
		count++;
	}
}

void SelectTeachers()
{
	int UserInput = 1;
	ofstream myfile ("Recipients.txt");
	while(UserInput != 0)	
	{
		cout << "\n(0 to finish) Choose a recipient: ";
		cin >> UserInput;
		if (myfile.is_open())
		{
			if(UserInput == 0)
			{
				cout << "\n\t[\tRecipients saved to file 'Recipients.txt'\t]\t\n\n";
			}
			else
			{
				myfile << Teachers[UserInput - 1] << endl;
				cout << "\n\t[\t" << Teachers[UserInput - 1] << " added to recipients list" << "\t]\t" << endl;
			}
		}
		else cout << "Unable to open file";
	}
	myfile.close();
}