没有输出啊
<!DOCTYPE HTML>
<html >
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>流程控制语句</title>
<script type="text/javascript">
var infos=new Array;
infos=[["小A","女","21","大一"],
["小B","男","23","大三"],
["小C","男","24","大四"],
["小D","女","21","大一"],
["小E","女","22","大四"],
["小F","男","21","大一"],
["小G","女","22","大二"],
["小H","女","20","大三"],
["小I","女","20","大一"],
["小J","男","20","大三"]
]
//第一步把之前的数据写成一个数组的形式,定义变量为
for(i=0;i<infos.length;i++)
{if(infos[i][3])==="大一"&&infos[i][1]==="女"){
document.write(姓名是:+infos[i][0])
}}
//第一次筛选,找出都是大一的信息
//第二次筛选,找出都是女生的信息
</script>
</head>
<body>
</body>
</html>