var imgMaxNum = 6;
var img_path = "./common/";
var randNum = Math.floor( Math.random() * imgMaxNum );
document.write('<img src=\"'+img_path+'p'+randNum+'.jpg\" />');
/*
new Element.hide('flash');
new Effect.Appear('flash');
*/
new Element.hide($('flash'));
new Effect.Appear($('flash'));