Calculate total time in office from checkin timestamp and checkout timestamp

[hubertdenie]

I have an excel list with name of employee, check-in timestamp (yyyy-mm-dd hh-mm-ss AM) and check-out time (yyyy-mm-dd hh-mm-ss AM). The timestamps are not marked as checkin or checkout unfortunately. I would like to calculate the time difference between the lowest time of date X and the latest time of date x per person. Furthermore, its important to note that sometimes employees forget to checkout.

Any suggestions?

Name	Date	Time	Device#	Operating Time
金峻	2017/12/1	9:24:00 AM	001	2017/12/1 9:23:48
金峻	2017/12/1	6:09:00 PM	001	2017/12/1 18:09:27
金峻	2017/12/4	6:09:00 PM	001	2017/12/4 18:12:54
金峻	2017/12/5	8:21:00 AM	001	2017/12/5 8:24:23
金峻	2017/12/6	6:03:00 PM	001	2017/12/6 18:06:36
金峻	2017/12/7	9:05:00 AM	001	2017/12/7 9:08:11
金峻	2017/12/7	6:06:00 PM	001	2017/12/7 18:09:03

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