Timesheet with multiple jobs, how to display time per job

I work on several jobs during the day, but I often start one, then work on another, then go back to the first one so I have multiple sessions of my time for the same Job.

I have this:

Job#, time in, time out, total time, hours

jobA, 8:00 AM, 9:00 AM, 1:00, 1.00
jobB, 9:00 AM, 10:00 AM, 1:00, 1.00
jobA, 10:00 AM, 10:30 AM, 0:30, 0.50
jobC, 10:30 AM, 11:00 AM, 0:30, 0.50
jobB, 11:00 AM, 12:00 PM, 1:00, 1
jobA, 1:00 PM, 4:30 PM, 3:30, 3.50

I manually enter in the Job#, In, and Out.

I want to display time spent per job:

Job, hours
A, 5
B, 2
C, 0.5

So the hard part is to gather all the multiple sessions of the same job.

I've attached a the weekly timesheet that I'm using, the part that I'm asking about is the lower section of each day. Currently I have to manually enter the job# and hours per session to get my hours per job. It would be great if the lower section would auto-fill. In fact I wouldn't even need the session section at all, just the job#, and Hours per Job.

Any help would be greatly appreciated. Thanks!