数组取余分组

<?php
$uids = array(1,2,3,4,5,6,7);
$uids_num = count($uids);
$k = $j = 0;
$uids_group = array();
for ($i = 0; $i < $uids_num; $i++) {
    if (($i+1) % 2 == 0) {
        $uids_group[$k][$j] = $uids[$i];
        $k += 1;
        $j = 0;
    } else {
        $uids_group[$k][$j] = $uids[$i];
        $j++;
    }
}
print_r($uids_group);exit;