var banner = new Array();

banner.push('https://img11.hostingpics.net/pics/377818ban0.png');
banner.push('https://img11.hostingpics.net/pics/165984ban1fini.png');
banner.push('https://img11.hostingpics.net/pics/984527tours3fini.png');
banner.push('https://img15.hostingpics.net/pics/723345bannerv21.png');

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