guru。</font></td>
    </tr>
    <tr>
        <td valign="top">
            <nobr><font face="verdana" size="-2"><strong>${challenge.tags}</strong></font></nobr>
        </td>
        <td width="10">&nbsp;</td>
        <td valign="top"><font face="verdana" size="-1">题目的标签，例如 数据结构、深度优先搜索、动态规划、贪心算法、树。</font></td>
    </tr>
    <tr>
        <td valign="top">
            <nobr><font face="verdana" size="-2"><strong>${challenge.testCases}</strong><