PS5Q5 cs 111

#include <iostream>
using namespace std;

int main()
{

    int sum_num = 0;
    int input;

    cout << "Enter a positive, non-zero integer\n";
    cin >> input;
    if (input>0)
    {
        for (int x = 1; x <= input; x++)
            {
            sum_num += x;
            }
        cout << "Sum of numbers from 1 to ";
        cout << input << " is " << sum_num << endl;
    }
    else if (input == 0)
    {
        cout << "Hey, I said non-negative\n";
    }
    else
    {
        cout << "Hey, I said positive\n";
    }

    return 0;
}