/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
 *  (C) 2001 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */
#include "mpi.h"
#include <stdio.h>
#include "mpitest.h"

void addem(int *, int *, int *, MPI_Datatype *);

void addem(int *invec, int *inoutvec, int *len, MPI_Datatype * dtype)
{
    int i;
    for (i = 0; i < *len; i++)
        inoutvec[i] += invec[i];
}

int main(int argc, char **argv)
{
    int rank, size, i;
    int data;
    int errors = 0;
    int result = -100;
    int correct_result;
    MPI_Op op;

    MTest_Init(&argc, &argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &size);

    data = rank;
    MPI_Op_create((MPI_User_function *) addem, 1, &op);
    MPI_Reduce(&data, &result, 1, MPI_INT, op, 0, MPI_COMM_WORLD);
    MPI_Bcast(&result, 1, MPI_INT, 0, MPI_COMM_WORLD);
    MPI_Op_free(&op);
    correct_result = 0;
    for (i = 0; i < size; i++)
        correct_result += i;
    if (result != correct_result)
        errors++;

    MTest_Finalize(errors);
    return MTestReturnValue(errors);
}
