var a = /*something*/,
    b = /*something*/,
    c = /*something*/;
console.log(a,b,c);

I don't know how to use console.log. Could you explain or show it?

If you're using JavaScript, console.log(content) will output to the codewars console. Most test cases should have some standard output, too.

How can I know wether it works? I tried it. Didn't work. Or may be it works but just to see the result I need to use alert instead of return, or document.write, or something else?