$(function(){
	$(".s1").change(function(){
	var selectedId = $(this).children().children("option:selected").attr("class");
	var lastIndex = selectedId.length;
	selectedId = selectedId.substring(3,lastIndex);
		$.getJSON("city.json",function(json) {
			$(".s2").html("<option>市町村を選んでください</option>");
	          $.each(json.items, function(i,item){
				if(item.pid == selectedId){
					$('<option class="cid' + item.cid + '" value="' + item.city  + '" >' + item.city + '</option>').appendTo(".s2");
				}
	          });
		});
	$(".s2").removeAttr("disabled");
	});
});