Page 105 - Beginning PHP 5.3

Chapter 4: Decisions and Loops
elseif ( $pigeonY > $homeY )
$pigeonY--;
// Display the current map

echo ‘<div class=”map” style=”width: ‘ . $mapSize . ‘em;”><pre>’;
for ( $y = 0; $y < $mapSize; $y++ ) {

for ( $x = 0; $x < $mapSize; $x++ ) {
if ( $x == $homeX && $y == $homeY ) {
echo ‘<span class=”home”>+</span>’; // Home
} elseif ( $x == $pigeonX && $y == $pigeonY ) {
echo ‘<span class=”pigeon”>%</span>’; // Pigeon
} else {
echo ‘<span class=”empty”>.</span>’; // Empty square
}
echo ( $x != $mapSize - 1 ) ? “ “ : “”;
}

echo “\n”;
}

echo “</pre></div>\n”;
} while ( $pigeonX != $homeX || $pigeonY != $homeY );

?>
</body>
</html>

To try out the script, save it as homing_pigeon.php in your document root folder, and open the script’s
URL in your Web browser. You should see something like Figure 4-4. Each map represents the progress
of the pigeon (represented by the % symbol) toward its home (the + symbol). Reload the page to run a
new simulation, with the home and the pigeon in different positions.

If your page looks different, make sure your document root folder contains the common.css file
described in Chapter 2.

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