如何使用PHP动态跨表（colspan）？

I have slot times booking room like this :

07.00,07.55,08.50,09.45,10.40,11.35,12.30,13.00,13.55,14.50,15.45,16.40,17.35,18.30.

This is a booking time example :

Book Time Room A1 :

      ==> 1 : 07.00 - 09.45 ~ credit 3
      ==> 2 : 10.40 - 12.30 ~ credit 3
      ==> 3 : 13.00 - 15.45 ~ credit 3

note : 1 credit --> 55 minutes

And now I have an array :

Array Book Time :

$startBook[0] = 07.00, 
$startBook[1] = 10.40, 
$startBook[2] = 13.00, 
$endBook[0] = 09.45, 
$endBook[1] = 12.30, 
$endBook[2] = 15.45

I want to display the table like :

How I can set the colspan dynamically depend on the credit. The credit not always 3, it also can be 2 or 4.

This is the html :

<table>
    <tr>
        <td>Room</td>
        <td colspan="" >07.00</td>
        <td colspan="" >07.55</td>
        so on...
    </tr>
    <tr>
        <td>A1</td>
        <td colspan="..."></td>
        <td>09.45</td>
    </tr>
</table>

You have to check every starting booking hour.

<table border="1">
<tr>
    <th>Room</th>
<?php
$rooms = array("a", "b", "c", "d", "e", "f");
$hours = array('07.00','07.55','08.50','09.45','10.40','11.35','12.30','13.00','13.55','14.50','15.45','16.40','17.35','18.30');
$startBook = array('07.00', '10.40', '13.00');
$endBook = array('09.45', '12.30', '15.45');

// Header
foreach ($hours as $hourIndex => $hour) {
    echo "<th>$hour</th>";
}
echo "
</tr>";

foreach ($rooms as $room) {
    echo "<tr>
        <td>" .$room['name'] ."</td>";
    $indexCurrentBook = -1;
    $tdColspan = 0;

    // Cicle every hour
    foreach ($hours as $hourIndex => $hour) {
        // Checking if there is an open book
        if ($indexCurrentBook >= 0) {
            if ($hour == $endBook[$indexCurrentBook]) { // Checking for the current book as ended
                echo "<td colspan=\"$tdColspan\" class=\"booked\">booked</td>";
                $indexCurrentBook = -1;
            } else {
                $tdColspan++;
            }
        }

        if ($indexCurrentBook < 0) {
            // No open book, searching for a new one
            $tdColspan = 1;
            foreach($startBook as $startBookIndex => $startBookDate) {
                if ($hour == $startBookDate) {
                    $indexCurrentBook = $startBookIndex;
                }
            }

            // If nothing as found, I write a blank cell
            if ($indexCurrentBook < 0) echo "<td class=\"blank\">blank</td>";
        }
    }
    echo "</tr>";
} ?>
</table>

bat , thanks for your answer, I tried to execute your code with an array set like this :

$array = array("a", "b", "c", "d", "e", "f");
$hours=array('07.00','07.55','08.50','09.45','10.40','11.35','12.30','13.00','13.55','14.50','15.45','16.40','17.35','18.30');
$startBook = array('07.00', '10.40', '13.00');
$endBook = array('09.45', '12.30', '15.45');

but it's display the table like this (all room is booked) :

how I can display the hours...

*if the image not shown, this is the table displayed :

a | booked
b | booked
c | booked
d | booked
e | booked
f | booked