删除有序数组的重复元素，并返回元素的个数

$arr = array(1,2,3,3,4,5);
print_r(remove1($arr ));


//方法1
function remove1($arr){
    $count = count($arr);
    if ($count == 0 || $count == 1) {
        return $count;  
    }
    $i = 0;
    for ($j = 1; $j < $count; $j++) {
        if ($arr[$j] != $arr[$i]) {
            $i++;
            $arr[$i] = $arr[$j];
        }
    }
    return $i + 1;
}

//方法2
function remove2(&$nums) {
        $count = count($nums);
        if ($count == 0 || $count == 1) {
            return $count;
        }
        $lastvalue = null;
        $length = 0;
        foreach ($nums as $k => $v) {
            if ($v === $lastvalue) {
                unset($nums[$k]);
            }else {
               $lastvalue = $v;
               $length ++;
            }
        }
        return $length;
    }