jquery find cell value, if exists change cell, if not add new row

Any help would be greatly appreciated,

what i'm trying to achieve is when a number/text in input into the code box it searches the table, if found increments qty by one, if not found adds a new row counting the no column by 1

i already a some basic jQuery code but would rather not post beginners code lol

Thanks in advance.

<input type="text" style="width: 200px" id="code" name="code" />
<input id = "btnSubmit" type="submit" value="Release"/>
<table> <thead>
            <tr>
                <th>No</th>
                <th>Code</th>
                <th>Qty</th>

            </tr>
        </thead>
    <tbody>
        <tr>
            <td>1</td>
            <td>4444</td>
            <td>1</td>
        </tr>
        <tr>
            <td>2</td>
            <td>5555</td>
            <td>1</td>

        </tr>
        <tr>
            <td>3</td>
            <td>6666</td>
            <td>1</td>

        </tr>
  <tr>
            <td>4</td>
            <td>7777</td>
            <td>1</td>

        </tr>
    </tbody>
</table>