vygerevanie textu

function permutations($letters,$num){ $last = str_repeat($letters{0},$num); $result = array(); while($last != str_repeat(lastchar($letters),$num)){ $result[] = $last; $last = char_add($letters,$last,$num-1); } $result[] = $last; return $result; } function char_add($digits,$string,$char){ if($string{$char} <> lastchar($digits)){ $string{$char} = $digits{strpos($digits,$string{$char})+1}; return $string; }else{ $string = changeall($string,$digits{0},$char); return char_add($digits,$string,$char-1); } } function lastchar($string){ return $string{strlen($string)-1}; } function changeall($string,$char,$start = 0,$end = 0){ if($end == 0) $end = strlen($string)-1; for($i=$start;$i<=$end;$i++){ $string{$i} = $char; } return $string; } ?>