// JavaScript Document
function leftdisplay(image){
for(i=1;i<=4;i++){
   document.getElementById("z"+i).style.display='none';
}

document.getElementById("z"+image).style.display="block";

document.getElementById("z").src="http://images.dtcoalmine.com/templates/101248/elyy/2011sy_20111121_gx_z"+image+".gif";
}
function rightdisplay(image){
for(i=1;i<=5;i++){
   document.getElementById("y"+i).style.display='none';
}

document.getElementById("y"+image).style.display="block";

document.getElementById("y").src="http://images.dtcoalmine.com/templates/101248/elyy/2011sy_20111121_gx_y"+image+".gif";
}