//画像は0から連番で「imgDir」に保存
//urlArrayには0〜対応するURLを記述
var urlArray = new Array (

'http://www.leafkyoto.net/special/1012_machiya/index',
'http://www.leafkyoto.net/special/1202_beauty/index',
'http://www.leafkyoto.net/special/1203_gourmet/index',
'http://www.leafkyoto.net/special/1011_itarian/index',
'http://www.leafkyoto.net/special/1009_meibutsu/index',
'http://www.leafkyoto.net/special/1203_gourmet/index'
);

var imgDir = 'http://www.leafkyoto.net/img/top/rndm/';
var imgType = '.jpg';

var displayNum = Math.floor ( ( Math.random() * 100 ) ) % urlArray.length;

document.write ( '<a href="' + urlArray[displayNum] + '">' );
document.write ( '<img src="' + imgDir + displayNum + imgType + '" />' );
document.write ( '</a>' );