Find total completion time of jobs

I have two different part that requires 4 different jobs. the time requested by each job is reported in the matrix M. The raws represent the two different parts and the columns the time for each job. PART1 enter before PART2 and the machine can do just one job at at time, so Job1 on PART2 have to wait the finish of Job1 on PART1.

M = [2 3 4 4 ;
     4 2 4 2 ]

What I want to obtain is the time that is needed to process all the parts with all the jobs. By hand it result to be t=15

Does someone know how to calculate by using matlab? It would be really helpful with a FOR cycle, because in the real case I have lot of job as well as lot of part.

[darova]

Can't you please describe logic of calculations?

Why can't you just sum your jobs?

[Ted Shultz]

It looks like you are trying to find Max(finish time of all parts) - min (start time of all parts). You M matrix does not include start of strop times, so I belive addtional informaiton is needed.

[Walter Roberson]

https://www.win.tue.nl/~wscor/OW/2V300/H6.pdf