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Finding PI using MPI collective operations
Finding PI using MPI collective operations

This exercise presents a simple program to determine the value of pi. The algorithm suggested here is chosen for its simplicity. The method evaluates the integral of 4/(1+x*x) between 1/2 and 1/2. The method is simple: the integral is approximated by a sum of n intervals; the approximation to the integral in each interval is (1/n)*4/(1+x*x). The master process (rank 0) asks the user for the number of intervals; the master should then broadcast this number to all of the other processes. Each process then adds up every n'th interval (x = 1/2+rank/n, 1/2+rank/n+size/n,...). Finally, the sums computed by each process are added together using a reduction.

Complete the missing arguments in the following pseudo code. Choose either one of the following Fortran or C example.
MPI routines :