This code is supposed to calculate two user inputs by multiplying them. However, the output is consistently 0 instead of would normally be expected ie 5\*5=0. I am not sure why this is happening. Am I not passing the variables into the function correctly? I feel like I might not be properly understanding value vs. reference (I am currently learning javascript)

```
var x = document.getElementById("a").value;
var y = document.getElementById("b").value;
var button = document.getElementById("button");

button.addEventListener('click', function() {
    calculator(x,y);
}, false);

function calculator(a,b) {
    var output = a * b;
    document.getElementById("answer").innerHTML = output;
    console.log(output);
}

```