// ==================================================================
// Author: Jean-Michel Richer
// Email: jean-michel.richer@univ-angers.fr
// Date: Aug 2020
// Last modified: September 2026
// Purpose: Demonstrate basic reduce functionality by computing the
// sum of a floatting point values on each process
// ==================================================================
#include <unistd.h>
#include <unistd.h>  // for sleep

#include <cstdlib>
#include <iostream>
#include <sstream>
using namespace std;
#include "./ezmpi.hpp"
using namespace ez::mpi;

/**
 * run master and slaves
 */
void run(int argc, char* argv[]) {
    Process process(argc, argv);
    process.verbose(false);

    float local_data = process.id() + 1;

    process << "- local data=" << local_data << endl;

    float reduction = 0;

    // reduction must be performed outside the master and slaves
    process.reduce(local_data, reduction, MPI::SUM);

    // only the master will report the result
    if (process.is_master()) {
        cout << "reduction = " << reduction << endl;
    }

    process.logs(cout);
}

// ==============================================================
// version C++
// ==============================================================
int main(int argc, char** argv) {
    // call a function that contains the code for the master and
    // the slaves in order to avoid problems of initialization and
    // finalization of processes
    run(argc, argv);

    exit(EXIT_SUCCESS);
}