PHP数组转化问题

Question

Array
(
    [0] => Array
        (
            [0] => user-
            [1] => notice-
        )    [1] => Array
        (
            [0] => user-
            [1] => calendar-
            [2] => calendar-
        )    [2] => Array
        (
            [0] => notice-
            [1] => calendar-
        ))
想要的效果Array([0]=>'user-notice',[1]=>'user-calendar-calendar',[2]=>'user-calendar')

Answer 1

foreach($arr as $v) $ar[]=substr(join('',$v),0,-1);
print_r($ar);