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/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
#include "mpi.h"
#include <stdio.h>
#include "mpitest.h"
#define MAX_PROCESSES 10
int main(int argc, char **argv)
{
int rank, size, i, j;
int table[MAX_PROCESSES][MAX_PROCESSES];
int row[MAX_PROCESSES];
int errors = 0;
int participants;
MPI_Comm comm;
MTest_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
comm = MPI_COMM_WORLD;
/* A maximum of MAX_PROCESSES processes can participate */
if (size > MAX_PROCESSES) {
participants = MAX_PROCESSES;
MPI_Comm_split(MPI_COMM_WORLD, rank < MAX_PROCESSES, rank, &comm);
} else {
participants = size;
MPI_Comm_dup(MPI_COMM_WORLD, &comm);
}
if ((rank < participants)) {
int send_count = MAX_PROCESSES;
int recv_count = MAX_PROCESSES;
/* If I'm the root (process 0), then fill out the big table */
if (rank == 0)
for (i = 0; i < participants; i++)
for (j = 0; j < MAX_PROCESSES; j++)
table[i][j] = i + j;
/* Scatter the big table to everybody's little table */
MPI_Scatter(&table[0][0], send_count, MPI_INT, &row[0], recv_count, MPI_INT, 0, comm);
/* Now see if our row looks right */
for (i = 0; i < MAX_PROCESSES; i++)
if (row[i] != i + rank)
errors++;
}
MPI_Comm_free(&comm);
MTest_Finalize(errors);
return MTestReturnValue(errors);
}
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