WITH consecutive_seats AS (
    SELECT
        LINE_ID,
        SEAT_NO,
        LAG(SEAT_NO, 1) OVER (PARTITION BY LINE_ID ORDER BY SEAT_NO) AS prev_seat,
        LAG(SEAT_NO, 2) OVER (PARTITION BY LINE_ID ORDER BY SEAT_NO) AS prev_seat_2,
        RSV_STATUS
    FROM
        SEAT_RESERVE
    WHERE
        RSV_STATUS = '0'
),
grouped_seats AS (
    SELECT
        LINE_ID,
        SEAT_NO AS SEAT_F,
        LEAD(SEAT_NO, 2) OVER (PARTITION BY LINE_ID ORDER BY SEAT_NO) AS SEAT_T,
        ROW_NUMBER() OVER (PARTITION BY LINE_ID ORDER BY SEAT_NO) AS row_num
    FROM
        consecutive_seats
    WHERE
        SEAT_NO - prev_seat = 1
        AND prev_seat - prev_seat_2 = 1
),
valid_seats AS (
    SELECT
        LINE_ID,
        SEAT_F,
        SEAT_T
    FROM
        grouped_seats
    WHERE
        SEAT_T IS NOT NULL
)
SELECT
    LINE_ID AS LINE,
    SEAT_F,
    SEAT_T
FROM
    valid_seats
ORDER BY
    LINE_ID DESC,
    SEAT_F ASC;