back_d = new Image(); back_d.src = "image/back.gif";
back_a = new Image(); back_a.src = "image/back_a.gif";
next_d = new Image(); next_d.src = "image/next.gif";
next_a = new Image(); next_a.src = "image/next_a.gif";
home_d = new Image(); home_d.src = "image/home.gif";
home_a = new Image(); home_a.src = "image/home_a.gif";


function go(j){
	if (j == 1){
		document.back.src = back_d.src;
	} else if (j == 2){
		document.back.src = back_a.src;
	} else if (j == 3){
		document.next.src = next_d.src;
	} else if (j == 4){
		document.next.src = next_a.src;
	} else if (j == 5){
		document.home.src = home_d.src;
	} else if (j == 6){
		document.home.src = home_a.src;
	}
}