JSFiddle - React, Tailwind, and code Playground

HTML

<table>
<tr class="parent_4">
<td> </td>
<td colspan="1">
  <select class="lesson" line="1" name="lesson[4][]" spellcheck="true">
 
</td>
<td style="text-align: center; padding: 0px;"> </td>
<td style="text-align: center; padding: 0px;"> </td>
<td style="text-align: center; padding: 0px;"> </td>
<td style="text-align: center; padding: 0px;">
  <input type="text" value="3" name="time[4][11][4]" style="width:15px;" spellcheck="true">
</td>
<td style="text-align: center; padding: 0px;">
  <input type="text" value="3" name="time[4][11][5]" style="width:15px;" spellcheck="true">
</td>
<td style="text-align: center; padding: 0px;">
  <input type="text" value="3" name="time[4][11][6]" style="width:15px;" spellcheck="true">
</td>
<td style="text-align: center; padding: 0px;">
  <input type="text" value="3" name="time[4][11][7]" style="width:15px;" spellcheck="true">
</td>
</tr>
</table>

JavaScript

var addedInput = $('.parent_4');
var cells = [];
var cell = 1;
addedInput.children('td').each(function(){
    if($(this).has('input').length){
        cells.push('ячейка ' + cell + ' непустая\n' + $(this).val())
    }
    else{
        cells.push('ячейка ' + cell + ' пустая\n');
    }
    cell++;
});
alert(cells)