I have an excel sheet containing the Entry and Exit time for users from bio metric software. I want to find how much time the user had stayed i.e. sum of difference between entry and exit times, but some time the user has to puch twice as the bio metric software doesn't accepts its login(like line 3 & 4 and 9 & 10 in the below shown table). In that case the difference should be done taking the last repeting Entry and last repeating Exit.
Please refer the snapshot below:
Date/Time Entry/Exit Badge Reader
7/10/2014 09:36:46 Entry 773821 BAN-IOS-2F-IBS-TS-IN NEW
7/10/2014 11:22:42 Exit 773821 BAN-IOS-2F-IBS-TS-OUT NEW
7/10/2014 11:27:34 Entry 773821 BAN-IOS-2F-IBS-TS-IN NEW
7/10/2014 11:27:42 Entry 773821 BAN-IOS-2F-IBS-TS-IN NEW
7/10/2014 12:59:24 Exit 773821 BAN-IOS-2F-IBS-TS-OUT NEW
7/10/2014 13:57:10 Entry 773821 BAN-IOS-2F-IBS-TS-IN NEW
7/10/2014 15:56:42 Exit 773821 BAN-IOS-2F-IBS-TS-OUT NEW
7/10/2014 16:24:19 Entry 773821 BAN-IOS-2F-IBS-TS-IN NEW
7/10/2014 17:25:56 Exit 773821 BAN-IOS-2F-IBS-TS-OUT NEW
7/10/2014 17:26:56 Exit 773821 BAN-IOS-2F-IBS-TS-OUT NEW
Please help in calculating the time the user has stayed in his desk from the data in the excel sheet.