Sum if number in column is the same, do another sum if it is different

I have the following datafile were B are participants (participant n.2 and participant n.4) and F is the number of behaviours. From this datafile I need to derive another datafile where each row is one participant (so in this case I would have a row for n.2 and a row for .4 and F would be the sum of the behaviours (so in this case it would be 0 and 7) OF EACH PARTICIPANT

FROM THIS -->

B F

2 0
2 0
4 5
4 1
4 1

-->TO THIS

2 0
4 7

How do I do this in the most economic way possible (I have hundreds of rows and 80 participants and I don't want to do the sum for each participant separately...)?

--> How do I sum the numbers in column F "in groups" according to the number on column B (if it is the same, then sum it, if not then create another row and another sum)??


Your help would be greatly appreciated!!!
Thank you

Welcome to the forum.

Are you looking for the SUMIF() function maybe?

http://www.excelfunctions.net/ExcelSumif.html

The numbers on B are not just 2 and 4, they change, so how can I use the sum if function?

I would advise zbor's solution, use Pivot Tables