Multiple reducers

Hi,

I'm working on Retail domain project.
In this project we have three separate goals to achieve, whereas the input data is same. So to handle this in Mapred code(java) do we have to write three separate Map reduce programs(Mapper,reducer,driver) each or is it possible to handle all the three goals with multiple reducers in a single Map reduce job.
If we have to follow the second method, then I need some guidance, so please share some sample code logic for the same.