Write a program that reads 2 numbers in c++

 Write a program that reads 2 numbers and print their + - * / as following:

My code:

#include<iostream>
using namespace std;
#include<exception>

void menu();
int add(int a, int b);
int sub(int a, int b);
int mult(int a, int b);
int Div(int a, int b);
int avg(int a, int b);
bool IsZero(int a, int b);

void main()
{
	int choice;
	do
	{
		menu();
		int a, b;
		//int choice;
		cout << "\t\t\tEnter your choice: ";
		cin >> choice;
		cout << "\t\t\t--------------------------" << endl;
		switch (choice)
		{
		case 1:
			cout << "\t\t\tEnter Number #1: ";
			cin >> a;
			cout << "\t\t\tEnter Number #2: ";
			cin >> b;
			cout << "\t\t\tResult: " << add(a, b) << endl;
			cout << "\t\t\t--------------------------" << endl;
			break;
		case 2:
			cout << "\t\t\tEnter Number #1: ";
			cin >> a;
			cout << "\t\t\tEnter Number #2: ";
			cin >> b;
			cout << "\t\t\tResult: " << sub(a, b) << endl;
			cout << "\t\t\t--------------------------" << endl;
			break;
		case 3:
			cout << "\t\t\tEnter Number #1: ";
			cin >> a;
			cout << "\t\t\tEnter Number #2: ";
			cin >> b;
			cout << "\t\t\tResult: " << mult(a, b) << endl;
			cout << "\t\t\t--------------------------" << endl;
			break;
		case 4:
			cout << "\t\t\tEnter Number #1: ";
			cin >> a;
			cout << "\t\t\tEnter Number #2: ";
			cin >> b;
			cout << "\t\t\tResult: " << Div(a, b) << endl;
			cout << "\t\t\t--------------------------" << endl;
			break;
		case 5:
			cout << "\t\t\tEnter Number #1: ";
			cin >> a;
			cout << "\t\t\tEnter Number #2: ";
			cin >> b;
			cout << "\t\t\tResult: " << avg(a, b) << endl;
			cout << "\t\t\t--------------------------" << endl;
			break;
		case 6:
			cout << "\t\t\tSee you later!\n";
			cout << "\t\t\t--------------------------" << endl;
			break;
		default:
			cout << "\t\t\tPlease, choose from menu.";
			cout << "\t\t\t--------------------------" << endl;
			break;
		}
		cout << "\n\n";
	} while (choice!=6);
	
	
}
//menu
void menu()
{
	cout << "\t\t\t -------------------------" << endl;
	cout << "\t\t\t| Program Math operations |" << endl;
	cout << "\t\t\t -------------------------" << endl;
	cout << "\t\t\t1- Add numbers.\n";
	cout << "\t\t\t2- Sub numbers.\n";
	cout << "\t\t\t3- Mult numbers.\n";
	cout << "\t\t\t4- Div numbers.\n";
	cout << "\t\t\t5- Avg numbers.\n";
	cout << "\t\t\t6-End program.\n";
	cout << "\t\t\t--------------------------" << endl;
}
//Add
int add(int a, int b)
{
	return a + b;
}
//sub
int sub(int a, int b)
{
	return a - b;
}
//mult
int mult(int a, int b)
{
	return a * b;
}
//div
int Div(int a, int b)
{
	return a / b;
}
//Avg
int avg(int a, int b)
{
	int c;
	c = a + b;
	return c / 2;
}