I don't know what's wrong. I'm trying to make a function that takes the power of a number but I get undefined instead of the result.

```
function power (base, exponent) {
for (var k=0; k<exponent; k++) {
var multiply=[];
multiply.push(base);
}
for (var i=0; i<multiply.length; i++) {
sum = 1;
sum = sum * multiply[i];
}
}
console.log(power(2,3));
```