// JavaScript Document

function changeBlock(){
var ID=new Array()
ID[1]='../_img/intro/01_00_A.jpg'
ID[2]='../_img/intro/01_00_B.jpg'
ID[3]='../_img/intro/01_00_C.jpg'
ID[4]='../_img/intro/01_00_D.jpg'

var change=Math.floor(Math.random()*ID.length)
if (change==0)
change=1
document.write('<img src="'+ID[change]+'">')
}
changeBlock()