a. Values tend to be computed well in advance before they are used.

b. The control structure is somewhat ambiguous, making it difficult to predict which data will be needed by each processor beforehand. 

In a Shared Memory Architecture, multiple processors can read and write data from the same location. Message Passing Architecture allows an alternate method for communication and movement of data among multiprocessors (compared to shared memory multiprocessor systems): There is no global memory so it provides a way to move data from one local memory to another by means of message passing. With all other factors being constant, for the following programs, would a shared memory multiprocessor or a message-passing multiprocessor be a better choice?