How to add <br> in string with substr() - php

Question

For the following code :
<?php
$word = 'SEKISUI';
// echo substr($word,0,-6)."<br>";
$length = (strlen($word)+1)-14;
$urut = 0;
for($i=$length;$i<1;$i++){
echo substr($word,$urut,$i).'<br>';
// echo $urut."-".$i."-".'<br>'; // Check Value
$urut++;
}
?>
Result :
S
E
K
I
S
U
why the letter "i" doesn't appear?
what is wrong with my code?
The result should look like:
S
E
K
I
S
U
I
Thank you for your attention...

Answer 1

I don't know if you NEED to use a 'for loop', but there is a better way to split a string into single characters.
Once you have the array you can do any operation to it, also join() the items in the array with a "\< br>" separator.
Try the following:
$word = 'SEKISUI';
$result = str_split($word);
$altogether = join("<br>",$result);

Answer 2

Not sure why you like the subtracting the length and not deal with positive numbers as much as possible.
In the syntax of substr(string,start,length),
Optional. Specifies the length of the returned string. Default is to
the end of the string. A positive number - The length to be returned
from the start parameter Negative number - The length to be returned
from the end of the string
So essentially your pointer on the end character is nevel counted.
if you run echo substr($word,0,-1)."<br>";, you will not get the end character as it is place of the start for the negative substr.
However, changing the substr length to 1 will give a valid string and not null or empty string
$word = 'SEKISUI';
// echo substr($word,0,-6)."<br>";
$length = (strlen($word)+1)-14;
$urut = 0;
for($i=$length;$i<1;$i++){
echo substr($word,$urut,1).'<br>';
// echo $urut."-".$i."-".'<br>'; // Check Value
$urut++;
}
However, I would prefer this approach, as this is much simpler.
$word = 'SEKISUI';
//echo substr($word,1,1)."<br>";
$length = strlen($word);
$urut = 0;
for($i = $urut; $i <= $length; $i++){
echo substr($word,$i,1).'<br>';
}