Calculate Date from shell script

I have a txt file which now has the following output

Sat Mar 6 04:00:01
Sat Mar 6 04:02:09
processing 585
Sat Mar 6 17:00:01
Sat Mar 6 17:00:58
processing 109
Sun Mar 7 04:00:01
Sun Mar 7 04:00:51
processing 309
Sun Mar 7 17:00:01
Sun Mar 7 17:00:41
processing 48

I want output as follows

Date     Time Take     No of Processing
Mar 6        02:09          585
Mar 6        0.57            109 
Mar 7        0.40             48

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