function tree_open(){

	tag_list = document.getElementsByTagName("div");

	for (i=0; i<tag_list.length-1; i++) {
		tag_list[i].style.display='block';
	}

}

function tree(no){
	z = document.getElementById("tree"+no).style.display;
	if ( z == "none" ) {
	    document.getElementById("tree"+no).style.display = 'block';
	} else {
	    document.getElementById("tree"+no).style.display = 'none';
	}
}