Javascript-форум - Динамически создаю таблицу

<table class="table-editor">
                        <tbody>
                        <tr class="normal-row">
                            <td><input type="text" size="2" maxlength="2" placeholder="a1,1"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a1,2"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a1,3"></td>
                        </tr>
                        <tr class="normal-row">
                            <td><input type="text" size="2" maxlength="2" placeholder="a2,1"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a2,2"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a2,3"></td>
                        </tr>
                        <tr class="normal-row">
                            <td><input type="text" size="2" maxlength="2" placeholder="a3,1"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a3,2"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a3,3"></td>
                        </tr>
                        <tr class="normal-row">
                            <td><input type="text" size="2" maxlength="2" placeholder="a4,1"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a4,2"></td>
                            <td><input type="text" size="2" maxlength="2" placeholder="a4,3"></td>
                        </tr>
                        </tbody>
                    </table>


<input id="addcol" type="button" value="Add Column" />
<input id="remcol" type="button" value="Reomve Column" />
<input id="addrow" type="button" value="Add row" />
<input id="remrow" type="button" value="Remove row" />

$('#addcol').click(function() {
    var $tablerow = $('table.table-editor').find('tr');
    count = 0;

    $tablerow.each(function(index, value){
        count += 1;
        var $listitem = $(this);
        n = parseInt($listitem.index());
        var $input = $('<input>', {
        type: 'text',
        maxlength: '2',
        placeholder: 'a'
    });
        var $newRow = $("<td>");
        $("table.table-editor tr:eq(" + n + ")").append($newRow.append($input));
        $("input:text").attr("size", "2");
    });
});

$('#remcol').click(function() {
    var $tablerow = $('table.table-editor').find('tr');
    
    $tablerow.each(function(index, value){
        $("table.table-editor tr:eq("+index+") td:eq(-1)").remove();
    });
});

$('#addrow').click(function() {
    
    var $input = $('<input>', {
        type: 'text',
        maxlength: '2',
        placeholder: 'a'
    });
    var $newRow = $("<td/>");
    $('table.table-editor').append("<tr></tr>");
    $('table.table-editor tr:eq(0) td').each(function(index, value){
        $("table.table-editor tr:eq(-1)").append($input.append($input));
        $("input:text").attr("size", "2");
    });
});

$('#remrow').click(function() {
    $('table.table-editor tr:eq(-1)').remove();
});

1. Некорректно работает добавление строк. Как это исправить?
2. Хочу, чтоб при добавлении новых ячеек в placeholder писалось а(номер столбца),(номер строки)

<!DOCTYPE html> <html> <head> <title>Untitled</title> <meta charset="utf-8"> <style type="text/css"> </style> <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script> <script> $(function() { var table = $(".table-editor"); $("#remcol").click(function() { $("tr td:last-child", table).remove() }); $("#addcol").click(function() { $("tr", table).append(function(i) { var num = "a" + (i + 1) + "," + ($("td", this).length + 1); return $("<td>").append($("<input/>", { attr: { size: "2", maxlength: "2", placeholder: num } })) }) }); $("#remrow").click(function() { $("tr:last-child", table).remove() }); $("#addrow").click(function() { var clone = $("tbody tr:last-child", table), first = !clone.length; clone = first ? $("<tr/>", {"class" : "normal-row"}) : clone.clone(); clone.appendTo(table); first && $("#addcol").trigger("click"); var num = "a" + (clone.index() + 1) + ","; $("input", clone).each(function(indx, input) { $(input).attr({ placeholder: num + ++indx }) }) }) }); </script> </head> <body> <table class="table-editor"> <tbody> <tr class="normal-row"> <td><input type="text" size="2" maxlength="2" placeholder="a1,1"></td> <td><input type="text" size="2" maxlength="2" placeholder="a1,2"></td> <td><input type="text" size="2" maxlength="2" placeholder="a1,3"></td> </tr> <tr class="normal-row"> <td><input type="text" size="2" maxlength="2" placeholder="a2,1"></td> <td><input type="text" size="2" maxlength="2" placeholder="a2,2"></td> <td><input type="text" size="2" maxlength="2" placeholder="a2,3"></td> </tr> <tr class="normal-row"> <td><input type="text" size="2" maxlength="2" placeholder="a3,1"></td> <td><input type="text" size="2" maxlength="2" placeholder="a3,2"></td> <td><input type="text" size="2" maxlength="2" placeholder="a3,3"></td> </tr> <tr class="normal-row"> <td><input type="text" size="2" maxlength="2" placeholder="a4,1"></td> <td><input type="text" size="2" maxlength="2" placeholder="a4,2"></td> <td><input type="text" size="2" maxlength="2" placeholder="a4,3"></td> </tr> </tbody> </table> <input id="addcol" type="button" value="Add Column" /> <input id="remcol" type="button" value="Remove Column" /> <input id="addrow" type="button" value="Add row" /> <input id="remrow" type="button" value="Remove row" /> </body> </html>