WITH SUM_RSV_STATUS AS (
    SELECT
        LINE_ID
        , SEAT_NO
        , RSV_STATUS
        , SUM(RSV_STATUS) OVER(
                ORDER BY
                    LINE_ID
                ROWS 2 PRECEDING
            ) AS SUM_RSV_STATUS
    FROM
        SEAT_RESERVE
)

SELECT
    LINE_ID AS LINE
    , SEAT_NO - 2 AS SEAT_F
    , SEAT_NO AS SEAT_T
FROM
    SUM_RSV_STATUS
WHERE
    SUM_RSV_STATUS = 0
ORDER BY
    LINE DESC
    , SEAT_F ASC
;