Multiple line input... Multiple line output

[zerohero911]

I am wondering if I have an input file with multiple lines and each line needs to have an output (multi-line output) from a function, how would the input/output coding work?

Thanks

[MiiNiPaa]

Can you elaborate. I'm not sure I understand what you want.

[zerohero911]

For instance if I had a program that calculates mathematical expressions (stored as strings), how would I input multiple lines, each with a different math expression, from stdin so that the output(s) calculate(s) every input expression (outputs multiple answers)?

[MiiNiPaa]

std::string line;
while(std::getline(std::cin, line)) {
    if (line == "stop")
        break; //Additional way to stop input
    //I assume, your calculations are done in eval() functions which takes string argument
    std::cout << eval(line);
}