Rising Temperature

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Leetcode

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Rising Temperature

Return the ids of days where the temperature is higher than the previous day.

Acceptance 100%

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Problem Statement

You are given a weather table with daily temperature readings. For each day, find the row(s) whose temperature is strictly higher than the temperature recorded on the previous calendar day.

Return the identifiers of those days.

The result can be returned in any order unless the platform specifies otherwise.

Input Format

You are given a table Weather with columns:

id — unique row id
recordDate — date of the reading
temperature — daily temperature

Dates are unique in the table.

Output Format

Return a table with a single column:

id — the ids of the rows where temperature > previous day's temperature

Constraints

recordDate values are unique.
Compare each row only with the immediately previous calendar day.
Only rows with a valid previous day record can qualify.

Examples

Sample cases returned by the problem API.

Example 1

Input

Weather table
| id | recordDate | temperature |
|----|------------|-------------|
| 1  | 2015-01-01 | 10          |
| 2  | 2015-01-02 | 25          |
| 3  | 2015-01-03 | 20          |
| 4  | 2015-01-04 | 30          |

Output

| id |
|----|
| 2  |
| 4  |

Explanation

2015-01-02 is warmer than 2015-01-01.
2015-01-04 is warmer than 2015-01-03.
2015-01-03 is not warmer than 2015-01-02.

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