Message Duration Calculation

You are given multiple test cases. Each test case consists of a list of timestamps in the format YYYY-MM-DD HH:MM:SS. Your task is to calculate the total duration in seconds between the earliest and the latest timestamp in each test case.

The duration is computed using the formula:

\(\text{duration} = \text{max_timestamp} - \text{min_timestamp}\)

If a test case contains no timestamps or only one timestamp, the answer is 0.

inputFormat

The input is read from standard input (stdin) with the following format:

• The first line contains an integer T — the number of test cases.
• For each test case:
• The first line contains an integer N — the number of timestamps.
• The next N lines each contain a timestamp string in the format YYYY-MM-DD HH:MM:SS.

outputFormat

For each test case, output a single line containing an integer — the duration in seconds, computed as the difference between the maximum and minimum timestamps. The result should be printed to standard output (stdout).

## sample

2
3
2023-04-23 10:00:00
2023-04-23 10:30:00
2023-04-23 11:00:00
5
2023-03-15 08:00:00
2023-03-15 08:15:00
2023-03-15 08:15:00
2023-03-15 09:45:00
2023-03-15 10:00:00

3600
7200

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