Check words if they are composed of Consecutive Alphabetic Characters - php

Question

I take a sentence as input like this:
abcd 01234 87 01235
Next, I have to check every word to see if its characters are consecutive in the alphabet. The output looks like this:
abcd 01234
Well, 01235 contains consecutive chars, but the whole word ALSO contains non-consecutive chars (35), so it's not printed on the screen.
So far I wrote this:
function string_to_ascii($string)
{
$ascii = NULL;
for ($i = 0; $i < strlen($string); $i++)
{
$ascii[] = ord($string[$i]);
}
return($ascii);
}
$input = "abcd 01234 87 01235";
//first, we split the sentence into separate words
$input = explode(" ",$input);
foreach($input as $original_word)
{
//we need it clear
unset($current_word);
//convert current word into array of ascii chars
$ascii_array = string_to_ascii($original_word);
//needed for counting how many chars are already processed
$i = 0;
//we also need to count the total number chars in array
$ascii_count = count($ascii_array);
//here we go, checking each character from array
foreach ($ascii_array as $char)
{
//if IT'S THE LAST WORD'S CHAR
if($i+1 == $ascii_count)
{
//IF THE WORD HAS JUST 1 char, output it
if($ascii_count == 1)
{
$current_word .= chr($char);
}
//IF THE WORDS HAS MORE THAN 1 CHAR
else
{
//IF PREVIOUS CHAR CODE IS (CURRENT_CHAR-1) (CONSECUTIVE, OUTPUT IT)
if(($char - 1) == $ascii_array[($i-1)])
{
$current_word .=chr($char);
}
}
}
//IF WE AREN'T YET AT THE ENDING
else
{
//IF NEXT CHAR CODE IS (CURRENT_CHAR+1) (CONSECUTIVE, OUTPUT IT)
if(($char + 1) == ($ascii_array[($i+1)]))
{
$current_word .=chr($char);
}
}
$i++;
}
//FINALLY, WE CHECK IF THE TOTAL NUMBER OF CONSECUTIVE CHARS is the same as THE NUMBER OF CHARS
if(strlen($current_word) == strlen($original_word))
{
$output[] = $current_word;
}
}
//FORMAT IT BACK AS SENTENCE
print(implode(' ',$output));
But maybe there is another way to do this, more simple?
sorry for bad spelling

Answer 1

This works...
$str = 'abcd 01234 87 01235';
$words = explode(' ', $str);
foreach($words as $key => $word) {
if ($word != implode(range($word[0], chr(ord($word[0]) + strlen($word) - 1)))) {
unset($words[$key]);
}
}
echo implode(' ', $words);
CodePad.
Basically, it grabs the first character of each word, and creates the range of characters which would be the value if the word consisted of sequential characters.
It then does a simple string comparison.
For a more performant version...
$str = 'abcd 01234 87 01235';
$words = explode(' ', $str);
foreach($words as $key => $word) {
foreach(str_split($word) as $index => $char) {
$thisOrd = ord($char);
if ($index > 0 AND $thisOrd !== $lastOrd + 1) {
unset($words[$key]);
break;
}
$lastOrd = $thisOrd;
}
}
echo implode(' ', $words);
CodePad.
Both these examples rely on the ordinals of the characters being sequential for sequential characters. This is the case in ASCII, but I am not sure about other characters.