↑ Try using arrow keys, home and end buttons, tabulating from one field to another and deleting with backspace in fields above. ↑
<div id="some-inputs">
<input type="text" maxlength="3" placeholder="3 chars" />
<input type="text" maxlength="4" placeholder="4 chars" />
<input type="text" maxlength="2" placeholder="2 chars" />
<input type="text" maxlength="2" placeholder="2 chars" />
<input type="text" maxlength="5" placeholder="5 chars" />
<input type="text" maxlength="5" placeholder="5 chars" />
</div>
<script type="text/javascript">
$('#some-inputs input').joinInputs()
</script>