求帮帮忙，解决一个问题

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <script type="text/javascript" src="../../js/jquery-1.9.1.js"></script>
    <script type="text/javascript" src="../../js/jquery-1.9.1.min.js"></script>
    <script>
        var a = 2;
        $(function(){
            $("tr").css("display","none")
        })
        function search(){
            $("tr").css("display","none")
            $("tr").each(function(index,o){
                if($("input").val()==$(this).children("td:first").text()){
                    $("tr:eq("+index+")").css("display","table")
                }
            })
        }
    </script>
</head>
<body>
    <input type="text" name="key">  <button onclick="search()">查找</button>
    <table border="1" cellspacing="0">
        <tr>
            <td>0</td>
            <td>哈哈0</td>
            <td>哈哈</td>
        </tr>
        <tr>
            <td width="50">1</td>
            <td width="100">哈哈1</td>
            <td width="100">哈哈</td>
        </tr>
        <tr>
            <td>2</td>
            <td>哈哈2</td>
            <td>哈哈</td>
        </tr>
        <tr>
            <td>3</td>
            <td>哈哈3</td>
            <td>哈哈</td>
        </tr>
        <tr>
            <td>4</td>
            <td>哈哈4</td>
            <td>哈哈</td>
        </tr>
    </table>
</body>
</html>