怎么用c++做一个小程序

#include <iostream>
using namespace std;

int main() {
    cout << "Hello, World!";
    return 0;
}

#include <iostream>
using namespace std;

int main() {
    int num1, num2, sum;
    cout << "Enter two numbers: ";
    cin >> num1 >> num2;
    sum = num1 + num2;
    cout << "Sum is: " << sum;
    return 0;
}