Basic C++ Calculator (Addition)

#include <cstdlib>
#include <iostream>
#include <string>

using namespace std;

int main()
{
    bool userType = true;

    do{
    int a;
    int b;
    int sum;

    cout << "Enter a number: ";
    cin >> a;

    cout << "Enter another number: ";
    cin >> b;

    sum = a + b;

    cout << "Answer: " << sum << "  :)" << endl;
    system("pause");
    }while(userType = true);


    return 0;
}