where is mistake ? php letter matrix boggle - php

Question

I find theese php codes here, but codes aren't working correctly. it seems that the if(isset($words[$word])) doesn't go through as I always get an empty results array
$boggle = "fxie
amlo
ewbx
astu";
$alphabet = str_split(str_replace(array("\n", " ", "\r"), "", strtolower($boggle)));
$rows = array_map('trim', explode("\n", $boggle));
$dictionary = file("C:/dict.txt");
$prefixes = array(''=>'');
$words = array();
$regex = '/[' . implode('', $alphabet) . ']{3,}$/S';
foreach($dictionary as $k=>$value) {
$value = trim(strtolower($value));
$length = strlen($value);
if(preg_match($regex, $value)) {
for($x = 0; $x < $length; $x++) {
$letter = substr($value, 0, $x+1);
if($letter == $value) {
$words[$value] = 1;
} else {
$prefixes[$letter] = 1;
}
}
}
}
$graph = array();
$chardict = array();
$positions = array();
$c = count($rows);
for($i = 0; $i < $c; $i++) {
$l = strlen($rows[$i]);
for($j = 0; $j < $l; $j++) {
$chardict[$i.','.$j] = $rows[$i][$j];
$children = array();
$pos = array(-1,0,1);
foreach($pos as $z) {
$xCoord = $z + $i;
if($xCoord < 0 || $xCoord >= count($rows)) {
continue;
}
$len = strlen($rows[0]);
foreach($pos as $w) {
$yCoord = $j + $w;
if(($yCoord < 0 || $yCoord >= $len) || ($z == 0 && $w == 0)) {
continue;
}
$children[] = array($xCoord, $yCoord);
}
}
$graph['None'][] = array($i, $j);
$graph[$i.','.$j] = $children;
}
}
function to_word($chardict, $prefix) {
$word = array();
foreach($prefix as $v) {
$word[] = $chardict[$v[0].','.$v[1]];
}
return implode("", $word);
}
function find_words($graph, $chardict, $position, $prefix, $prefixes, &$results, $words) {
$word = to_word($chardict, $prefix);
if(!isset($prefixes[$word])) return false;
**if(isset($words[$word])) {
$results[] = $word;
}**
foreach($graph[$position] as $child) {
if(!in_array($child, $prefix)) {
$newprefix = $prefix;
$newprefix[] = $child;
find_words($graph, $chardict, $child[0].','.$child[1], $newprefix, $prefixes, $results, $words);
}
}
}
$solution = array();
find_words($graph, $chardict, 'None', array(), $prefixes, $solution);
print_r($solution);

Answer 1

When you call find_words() at the end, you are only passing 6 parameters
find_words($graph, $chardict, 'None', array(), $prefixes, $solution);
The variable $words, is the 7th parameter in your definition of find_words()
function find_words($graph, $chardict, $position, $prefix, $prefixes, &$results, $words) {
Hence, $words will always be empty, and isset($words[$word]) will always be false