#include<iostream>
using namespace std;

class calculator
{
public:

	void addition();

	void subtraction();

	void multiplication();

	void division();

private:

	double sum;

	double product;

	double sub;

	double tot;
};

int main ()
{
	calculator digits;
	int choice;

	do
	{
		cout << endl;
		cout << "Welcome to the CompE 46 Calculator, where magic happens with digits!" << endl;
		cout << "Choose 1 for Addition." << endl;
		cout << "Choose 2 for Subtraction." << endl;
		cout << "Choose 3 for Multiplication." << endl;
		cout << "Choose 4 for Division." << endl;
		cout << "Choose 0 to quit this program." << endl;

		cin  >> choice;

		switch (choice)
		{
			case 1:
				digits.addition();
				break;
			case 2:
				digits.subtraction();
				break;
			case 3:
				digits.multiplication();
				break;
			case 4:
				digits.division();
				break;
			case 0:
				exit(0);
			default:
				cout << "Your choice was INVALID. Select one of the choices listed." << endl;
		}
	} while (choice != 4);



	return 0;
}

void calculator::addition()
{
	double a, b;

	cout << "Welcome to the ADDITION SECTION!" << endl;
	cout << "Please select a number and press Enter." << endl;
	cin  >>  a;
	cout << "Select a number you want to add to the number entered in the previous step." << endl;
	cin  >> b;
	cout << endl;
	
	sum = a + b;

	cout << a << " plus " << b << " equals " << sum << endl;
}

void calculator::subtraction()
{
	double c, d;

	cout << "Welcome to the SUBTRACTION SECTION!" << endl;
	cout << "Please select a number and press Enter." << endl;
	cin  >> c;
	cout << "Select a number you want to subtract to the number entered in the previous step." << endl;
	cin  >> d;
	cout << endl;

	sub = c - d;

	cout << c << " minus " << d << " equals " << sub << endl;

}

void calculator::multiplication()
{
	double e, f;

	cout << "Welcome to the MULTIPLICATION SECTION!" << endl;
	cout << "Please select a number and press Enter." << endl;
	cin  >> e;
	cout << "Select a number you want to multiply to the number entered in the previous step." << endl;
	cin  >> f;
	cout << endl;
	
	product = e * f;

	cout << e << " times " << f << " equals " << product << endl;

}

void calculator::division()
{
	double g, h;

	cout << "Welcome to the DIVISION SECTION!" << endl;
	cout << "Please select a number and press Enter." << endl;
	cin  >> g;
	cout << "Select a number you want to divide to the number entered in the previous step." << endl;
	cin  >> h;
	cout << endl;

	tot = g / h;

	cout << g << " divided by " << h << " equals " << tot << endl;
}