[codewar] Extract the domain name from a URL

https://www.codewars.com/kata/514a024011ea4fb54200004b

코드를 입력하세요
const domainName = function (arr) {
    var hey = arr.split('.');

    var numvv = 0;
    console.log(hey)
    var num = hey.forEach((element, index) => {
        //console.log(index, element)
        if (element.includes('www')) {
            // console.log("?")
            numvv = index + 1;

        }




    });
    var ok = (hey[numvv]);
    var ok_re = (ok.split('/'))
    return (ok_re[ok_re.length - 1])
}