var banner = new Array();

banner[0]='https://i.imgur.com/VIydw9z.png';
banner[1]='https://i.imgur.com/gEDJbkc.png';
banner[2]='https://i.imgur.com/WlqmVzB.png';
banner[3]='https://i.imgur.com/A3ak0Km.png';
banner[4]='https://i.imgur.com/CvI1SI9.png';

document.getElementById('i_logo').src= banner[Math.floor(Math.random()*banner.length)];