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            var hours = parseInt(leftTime / 1000 / 60 / 60 % 24, 10); //计算剩余的小时

            var minutes = parseInt(leftTime / 1000 / 60 % 60, 10);//计算剩余的分钟

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<table style="width: 100%; height: 100%;" id="tab" border="1" cellpadding="1" cellspacing="1">

        <tr style="background-color: #CCC;">

            <th>学号</th>

            <th>姓名</th>

            <th>性别</th>

            <th>年龄</th>

            <th>入学时间</th>

            <th>倒计时</th>

        </tr>

        <tr>

            <td>1</td>

            <td>李斯</td>

            <td>男</td>

            <td>22</td>

            <td>2018/2/8 11:28:09</td>

            <td>已入学</td>

        </tr>

        <tr>

            <td>2</td>

            <td>王倩</td>

            <td>女</td>

            <td>20</td>

            <td>2018/3/7 11:28:09</td>

                 <td>已入学</td>

        </tr>

        <tr>

            <td>3</td>

            <td>于谦</td>

            <td>男</td>

            <td>18</td>

            <td>2018/3/8 13:28:09</td>

                 <td>已入学</td>

        </tr>

        <tr>

            <td>4</td>

            <td>柳浪</td>

            <td>女</td>

            <td>19</td>

            <td>2018/3/8 11:40:20</td>

                <td>已入学</td>

        </tr>

        <tr>

            <td>5</td>

            <td>诸葛亮</td>

            <td>男</td>

            <td>20</td>

            <td>2018/3/8 12:30:39</td>

                <td>已入学</td>

        </tr>

        <tr>

            <td>6</td>

            <td>东方云</td>

            <td>女</td>

            <td>21</td>

            <td>2018/3/8 11:45:20</td>

              <td>已入学</td>

        </tr>

        <tr>

            <td>7</td>

            <td>公孙策</td>

            <td>男</td>

            <td>22</td>

            <td>2018/3/8 11:50:59</td>

             <td>已入学</td>

        </tr>

        <tr>

            <td>8</td>

            <td>宝清</td>

            <td>女</td>

            <td>23</td>

            <td>2018/3/8 13:28:47</td>

               <td>已入学</td>

        </tr>

        <tr>

            <td>9</td>

            <td>智育</td>

            <td>男</td>

            <td>20</td>

            <td>2018/3/8 13:08:09</td>

                <td>已入学</td>

        </tr>

        <tr>

            <td>10</td>

            <td>柳丝丝</td>

            <td>女</td>

            <td>21</td>

            <td>2018/3/8 14:28:09</td>

               <td>已入学</td>

        </tr>

    </table>