/**
* 获取字符串按序全排列(英文) e.g. abcd => a ab abc abcd b bc bcd c cd d
*
* @param $str
* @param string $separator
* @return array
*/
function getSortCombinations($str, $separator = ”) {
if ($separator !== ”) {
$chars = explode($separator, $str);
} else {
$chars = str_split($str);
}
$res = $chars;
$count = count($chars);
for ($i = 0; $i < $count – 1; $i++) {
$tmp = $chars[$i];
for ($j = $i + 1; $j < $count; $j++) {
$tmp = $tmp . $chars[$j];
$res[] = $tmp;
}
}
return $res;
}
/**
* 获取字符串按序全排列(中文)
*
* @param $str
* @return array
*/
function getSortCombinationsChinese($str) {
$chars = preg_split(‘/(?<!^)(?!$)/u’, $str);
$res = $chars;
$count = count($chars);
for ($i = 0; $i < $count – 1; $i++) {
$tmp = $chars[$i];
for ($j = $i + 1; $j < $count; $j++) {
$tmp = $tmp . $chars[$j];
$res[] = $tmp;
}
}
return $res;
}
