matrix.php

<?php

$a = 5; 
$b = 5;

for ($aa = 0; $aa <= $a; $aa++)
{    
    for ($bb = 0; $bb <= $b; $bb++)
    {
        if ($aa == 0 || $bb == 0)
        {
            $v = $aa + $bb;
        }
        else
        {
            $v = $aa * $bb;
        }
        
        printf("%5u", ($v . " "));
    }
    
    print "\n";
}