* Exercise : "Distributed matrix initialization"
- Broadcast only
- read matrix size n from command line
- only processor 0 can access argc and argv
- if argc < 2: ask for argument + everybody returns graciously
- if n > nProcs: complain + everybody returns graciously
- else: // more processes than columns
everybody allocates M, a matrix of size 2*n x n, storage by columns
- 0 <= i < n:
process_i initializes randomly the i-th column of M
- every process prints out M
- process_i sends the i_th column to everyone else
- every process prints out M