var pre="images/sah_"
var d=document

function on(pic){
    d[pic].src=pre+pic+"_on.jpg"
}

function off(pic){
    d[pic].src=pre+pic+"_off.jpg"
}

var myimages=new Array()
function loadpics(){
    for (i=0;i<loadpics.arguments.length;i++){
    myimages[i]=new Image()
    myimages[i].src=pre+loadpics.arguments[i]+"_on.jpg"
    }
}