Question

I am trying to create a simple multiplication grid in PHP

It should be of the format for example for a 2×2 grid:

0 1 2
1 1 2
2 2 4

My issue is getting it to start from 0.

This is my nested for loop so far:

 for($i=0;$i<=$_POST['rows'];$i++)
                {
                        echo "<tr>";
                        for($j=0;$j<=$_POST['columns'];$j++)
                        {
                                if($i==0)
                                {
                                        echo "<td>" . 1*$j . "</td>";
                                }
                                else
                                {
                                        $mult = $i * $j;
                                        echo "<td> $mult </td>";
                                }
                        }
                        echo "</tr>";
                }

But it gives the output:

0   1   2
0   1   2
0   2   4 

I need the column of 0’s to be appropriate.

Answer 1

The way you’re getting the top row of 0 1 2 3 is by that special-case on the X-axis. Do a similar special-case for the Y-axis ($j):

if ($i == 0) {
    ... 1 * $j ...
}
else if ($j == 0) {
    ... $i * 1 ...
}
else {
    ... $i * $j ...
}