php 地区分类排序算法

function typeArray($array){
        $con = null;
        foreach ($array as $k=>$v){
            $na[$k] = is_numeric($v[0]) ? $na[$v[0]].$k."|" : $k."|";
        }
        asort($na); //排序
        foreach ($na as $k=>$v){
          $s = substr_count($v,"|");
          $con .= str_repeat("-",($s-1)).$array[$k][1]."\n";
        }
        return $con;
    }