En liten miniräknare.

#include<iostream>

using std::cout;
using std::cin;

int main()
{
    int en_tal;
    int en_tall_till;
    int summa;
    
    cout << "Hello, please put in a number!\n";
    cin >> en_tal;
    cout << "One more please!\n";
    cin >> en_tall_till;
    
    summa = en_tal + en_tall_till;
    
    cout << "It is!\n";
    cout << summa;
    cout << "Well, goodbye!\n"
    
    
    system("PAUSE");
    return EXIT_SUCCESS;
}

 `;' before "system" 

cout << "Well, goodbye!\n"
    
    
    system("PAUSE");

cout << summa;

cout<<summa<<endl;
eller så kan du ta
cout<<summa<<"\n";

void main(void)
{
	int val = 1;

	cout	<< "Meny << endl
		<< "1. Addera" << endl
		<< "2. Subtrahera" << endl
		<< "3. Multiplicera" << endl
		<< "4. Dividera" << endl;
	cin	>> val;

	// Med switch :
	switch(val)
	{
		case 1:
			// I princip samma kod som ditt nuvarande program
			// eller kalla på en funktion som innehåller detta
			break;
		case 2:
			// Se ovan
			break;
		case 3:
			// Se ovan
			break;
		case 4:
			// Se ovan
			break;
	}

	// ELLER med if / else
	if(val == 1)
	{
		// Mysig kod
	}
	else if(val == 2)
	{
		// Se ovan
	}
	else if(val == 3)
	{
		// Se ovan
	}
	else // 4
	{
		// Se ovan
	}
}

#include<iostream>

using std::cout;
using std::cin;

int main()
{
    int val1;
    int val2;
    int val3;
    int val4;
    int summa;
    
    system("color 0A");
    cout << "1. Addera\n";
    cout << "2. Subtrahera\n";
    cout << "3. Dividera\n";
    cout << "4. Multiplicera\n";
    cin >> val1;
    if(val == 1)
    {
           cout << "Please put in one number!\n";
           cin >> val1;
           cout << "One more please.\n";
           cin >> val2;
           
           summa = tal1 + tal2;
           cout << "The numbers " << val1 << " + " << val2 << " = " << summa << "\n";
           }
           
    
    system("PAUSE");
    return EXIT_SUCCESS;
}