Complicated Star Pattern? - php

Question

Okay, so I have a unique problem that I ran into when trying to code a 5x3 star pattern. I can do the for loops to get the 5x3, that's easy. However I need something different than a square.
We can have a maximum of 15 stars. So printing out a full block would look like this:
* * *
* * *
* * *
* * *
* * *
But we can pass in a parameter for the number of stars that we want. So let's pass in 11 instead of 15. We should get:
* * *
* * *
* * *
* *
However, with 11 as my parameter the output is like this:
*
* *
* *
*
It prints out the correct number of rows with the incorrect number of stars. I know why this is, and it's because of the modulus in my code. I also tried a different approach, which printed out one less row than needed. I am stuck and not sure where to go from here.
Here is my code:
<?php
$num = 11;
$rows = ceil($num/3);
$count - 0;
for($j = 0; $j < $rows; $j++){
echo '<div class="row-fluid"><ul class="thumbnails">';
for($i = $num%3; $i < 3; $i++){
echo '*';
$count++;
}
$num-=$count;
echo '</ul></div>';
}
?>

Answer 1

With some simple PHP-Fu:
$stars = 11;
$row_length = 3;
$array = array_fill(0, $stars, '*');
$array = array_chunk($array, $row_length);
$table = '<table border="0">';
foreach($array as $row){
$table .= '<tr><td>'. implode('</td><td>', $row) .'</td></tr>';
}
$table .= '</table>';
echo $table;
Online demo.

Answer 2

The idea should be as simple as: keep drawing until you reach the target number.
So you could do this:
$num = 11;
for( $i=0; $i<$num; $i+=3) {
echo "<div class=\"row-fluid\"><ul class=\"thumbnails\">";
for( $j=0; $j<3 && $i+$j<$num; $j++) {
echo "*";
}
for( ; $j<3; $j++) { // finish the current row (optional, remove if not needed)
echo " ";
}
echo "</ul></div>";
}

Answer 3

Ooh a puzzle!
I don't know if using for was a requirement for your assignment, I prefer while.
$num_of_stars = 15;
$stars_per_row = 3;
while($num_of_stars > 0){
echo "*";
if($stars_per_row == 1){
$stars_per_row = 3;
echo "<br />";
}else{
$stars_per_row --;
}
$num_of_stars --;
}

Answer 4

I don't see why you would have to use two for-loops.
I would do something like this: (I noticed you don't have any <li>'s in your code) Of course you would have to set the class="thumbnails" to include list-style-type:none;
<?php
$num = 11;
$cols = 3;
echo '<div class="row-fluid"><ul class="thumbnails">';
$count = 0;
for($j = 0; $j < $num; $j++){
$count++;
echo '<li style="float:left;">*</li>';
if ($count>=$cols) {
$count = 0;
echo '<li style="clear:both;"></li>';
}
}
echo '</ul></div>';
?>

Answer 5

For this to work, this is what you need.
$num = 11;
$cols = 3;
$rows = ceil($num/$cols);
for($j=0;$j<$rows;$j++)
echo "<div class='row'>";
for($i=0;$i<$cols;$i++){
echo "*";
}
echo "</div>";
}
To show where you went wrong in your code. First, your definition of $count should be = not -. Next, your inner for loop is odd.
First loop through, $num is equal to 11. In your inner loop you set $i = $num%3 which is $i = 2. So the inner loop runs through once while $i++ < 3, echo's one star and increments count once. inner loop exits, you subtract $count from $num making $num=10 and row is completed, next outer loop iteration.
Next time the inner loop runs, $num is 10 so $i = $num%3 becomes $i=1. Inner loop runs 2 times while $i++ < 3, echo'ing 2 more stars and incrementing $count both times making it now 3. after the inner loop you subtract 3 more from $num making it 7 and row ends, outer loop continues.
Next inner loop, $num is 7 so $i = $num%3 becomes $i=1. Inner loop runs 2 times while $i++ < 3, echo'ing 2 more stars and incrementing $count both times making it now 5. after the inner loop you subtract 5 from $num making it now 2, row ends, outer loop continues.
Last iteration of the outer loop (row limit hit), $num is 2 so $i = $num%3 becomes $i=1. Inner loop runs once, echo's one star and inrement count once making it now 8. Inner loop finishes, you subtract 8 from $num making it now -6, row ends, outer loop ends.