a = 3// a=numbers of banners
var slump = Math.random();
var talet = Math.round(slump * (a-1))+1;
function create() {
        this.width = ''
        this.height = ''
        this.src = ''
        this.href = ''
        this.border = ''
        this.alt = ''
        this.under = ''
}
b = new Array()
for(var i=1; i<=a; i++) { b[i] = new create() }
b[1].src    = "http://rzinfo.net/ichat/images/banner/hui16.gif"
b[1].href   = "http://rzinfo.net/"
b[1].width  = "468"
b[1].height = "60"
b[1].border = "0"
b[1].alt    = "党的十六大"
b[1].under  = '党的十六大'

b[2].src    = "http://rzinfo.net/ichat/images/banner/kailiao.gif"
b[2].href   = "http://chat.rzinfo.net"
b[2].width  = "468"
b[2].height = "60"
b[2].border = "0"
b[2].alt    = "日照信息港--阳光聊天城"
b[2].under  = '阳光聊天城'

b[3].src    = "http://rzinfo.net/ichat/images/banner/rz888.gif"
b[3].href   = "http://www.rz888.com"
b[3].width  = "468"
b[3].height = "60"
b[3].border = "0"
b[3].alt    = "888便民服务网"
b[3].under  = '888便民服务网'

var strListad = "";
strListad += '<a href="'+b[talet].href+'" target="_blank">'
strListad += '<img src="'+b[talet].src+'" height='+b[talet].height
strListad += ' width='+b[talet].width+' border='+b[talet].border+' alt='+b[talet].alt+'>';
strListad += '</a>';

document.write(strListad);