function RemoveCharactersNeedToBeRemovedForAnagram(&$str1, &$str2) {
$TotalABCLetters = 26;
$count1 = array_fill(0,$TotalABCLetters,0);
$count2 = array_fill(0,$TotalABCLetters,0);
$size1 = strlen($str1);
$size2 = strlen($str2);
// count char frequency str1
for ($i = 0; $i < $size1; $i++) {
$count1[ord($str1[$i]) - ord('a')]++;
}
// count char frequency str2
for ($i = 0; $i < $size2; $i++) {
$count2[ord($str2[$i]) - ord('a')]++;
}
for ($i = 0; $i < $TotalABCLetters; $i++) {
if (abs($count1[$i] - $count2[$i]) != 0) {
$str1 = str_replace(chr($i + 97), '', $str1); // 'a' = 97 ascii code
$str2 = str_replace(chr($i + 97), '', $str2);
}
}
}
$str1 = "masterfx";
$str2 = "ksampret";
RemoveCharactersNeedToBeRemovedForAnagram($str1, $str2);
echo $str1 . "\n";
echo $str2 . "\n";
/*
run:
master
samret
*/