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/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
 *  (C) 2001 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */

#include <stdio.h>
#include "mpi.h"
#include "mpitest.h"

#define TABLE_SIZE 2

int main(int argc, char **argv)
{
    int rank, size;
    double a[TABLE_SIZE];
    struct {
        double a;
        int b;
    } in[TABLE_SIZE], out[TABLE_SIZE];
    int i;
    int errors = 0, toterrors;

    /* Initialize the environment and some variables */
    MTest_Init(&argc, &argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &size);

    /* Initialize the maxloc data */
    for (i = 0; i < TABLE_SIZE; i++)
        a[i] = 0;
    for (i = rank; i < TABLE_SIZE; i++)
        a[i] = (double) rank + 1.0;

    /* Copy data to the "in" buffer */
    for (i = 0; i < TABLE_SIZE; i++) {
        in[i].a = a[i];
        in[i].b = rank;
    }

    /* Reduce it! */
    MPI_Reduce(in, out, TABLE_SIZE, MPI_DOUBLE_INT, MPI_MAXLOC, 0, MPI_COMM_WORLD);
    MPI_Bcast(out, TABLE_SIZE, MPI_DOUBLE_INT, 0, MPI_COMM_WORLD);

    /* Check to see that we got the right answers */
    for (i = 0; i < TABLE_SIZE; i++)
        if (i % size == rank)
            if (out[i].b != rank) {
                printf("MAX (ranks[%d] = %d != %d\n", i, out[i].b, rank);
                errors++;
            }

    /* Initialize the minloc data */
    for (i = 0; i < TABLE_SIZE; i++)
        a[i] = 0;
    for (i = rank; i < TABLE_SIZE; i++)
        a[i] = -(double) rank - 1.0;

    /* Copy data to the "in" buffer */
    for (i = 0; i < TABLE_SIZE; i++) {
        in[i].a = a[i];
        in[i].b = rank;
    }

    /* Reduce it! */
    MPI_Allreduce(in, out, TABLE_SIZE, MPI_DOUBLE_INT, MPI_MINLOC, MPI_COMM_WORLD);

    /* Check to see that we got the right answers */
    for (i = 0; i < TABLE_SIZE; i++)
        if (i % size == rank)
            if (out[i].b != rank) {
                printf("MIN (ranks[%d] = %d != %d\n", i, out[i].b, rank);
                errors++;
            }

    /* Finish up! */
    MTest_Finalize(errors);
    return MTestReturnValue(errors);
}