# Consecutive Available Seats Problem

## Description

LeetCode Problem 603.

Several friends at a cinema ticket office would like to reserve consecutive available seats. Can you help to query all the consecutive available seats order by the seat_id using the following cinema table?

``````1
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| seat_id | free |
|---------|------|
| 1       | 1    |
| 2       | 0    |
| 3       | 1    |
| 4       | 1    |
| 5       | 1    |
``````

Your query should return the following result for the sample case above.

``````1
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| seat_id |
|---------|
| 3       |
| 4       |
| 5       |
``````

Note:

• The seat_id is an auto increment int, and free is bool (‘1’ means free, and ‘0’ means occupied.).
• Consecutive available seats are more than 2(inclusive) seats consecutively available.

## MySQL Solution

``````1
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select c1.seat_id
from cinema c1, cinema c2
where ((c1.seat_id = c2.seat_id+1) or
(c1.seat_id = c2.seat_id-1)) and
(c1.free = 1) and (c2.free = 1)
group by c1.seat_id
``````