#17MediumSQL· Window Functions

Consecutive Numbers

A sensor writes one reading per row into a log table. **Logs** | Column | Type | |---|---| | id | INT (primary key, increasing with time) | | num | INT | Rows are ordered by `id`. Find every value of `num` that appears in **at least three consecutive rows** (three rows next to each other in `id` order, all with the same `num`). Return a single column named `ConsecutiveNums`. Each qualifying value appears once, even if it has several separate runs. Order the result by `ConsecutiveNums` ascending.

Input format

Logs rows as [id, num]

Output format

Result rows as [ConsecutiveNums], ordered ascending; an empty array means no rows

Examples

Input: Logs = [[1, 4], [2, 4], [3, 4], [4, 2], [5, 4], [6, 2], [7, 2]]

Output: [[4]]

4 appears in rows 1, 2 and 3. The value 2 appears three times but never three rows in a row.

Input: Logs = [[1, 5], [2, 5], [3, 5], [4, 1], [5, 5], [6, 5], [7, 5]]

Output: [[5]]

5 has two separate runs of three, but is reported once.

Constraints

0 <= rows in Logs <= 10^5
id values are unique; they are consecutive integers in the tests, but a robust query should only rely on their order.
-10^6 <= num <= 10^6

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