var i = document.getElementsByClassName('r');
for(var z=0;z<i.length;z++){
    var url = i[z].getElementsByTagName('a');
console.log(url[0].href)
}

var h3 = document.getElementsByTagName('h2');
for(var i=0;i<h3.length;i++){
    var a = h3[i]. getElementsByTagName('a');
    console.log(a[0].href);
}