#include <iostream>
#include <string>
#include <sstream>
 
int main()
{
    std::string line;
    int sum, value;
 
    do
    {
        std::cout << "Enter a set of numbers, or a blank line to exit: ";
        if (!std::getline(std::cin, line) || line.empty())
            break;
 
        // read until end-of-line, calculating a running total of all values read
        std::istringstream iss(line);
        sum = 0;
        while (iss >> value)
            sum += value; // equivalent to sum = sum + value
 
        std::cout << "Sum is: " << sum << std::endl;
    }
    while (true);
 
    std::cout << "Good bye!" << std::endl;
    return 0;
}

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