Irregular layout of table label

introduce

utilize table In the label td Of rowspan Merge Columns ,colspan Merger line

A simple case

The code is as follows ：

<table border="1">
    <tr>
        <td>aa</td>
        <td rowspan="2">cc</td>
    </tr>
    <tr>
        <td>bb</td>
    </tr>
</table>

<table border="1">
    <tr>
        <td rowspan="2">cc</td>
        <td>aa</td>
    </tr>
    <tr>
        <td>bb</td>
    </tr>
</table>

<table border="1">
    <tr>
        <td>cc</td>
        <td>aa</td>
    </tr>
    <tr>
        <td colspan="2">bb</td>
    </tr>
</table>

<table border="1" cellpadding="0" cellspacing="0">
    <tr>
        <td rowspan="2">ccc</td>
        <td colspan="2">aaa</td>
    </tr>
    <tr>
        <td>bb</td>
        <td rowspan="2">vvv</td>
    </tr>
    <tr>
        <td colspan="2">eee</td>
    </tr>
</table>