MPI_my_var

// lab2MPI.cpp: определяет точку входа для консольного приложения.
//

#include "stdafx.h"
#include <mpi.h>
#include <iostream>
#include <vector>
#define iter_num 1
#define vec_size 10
using namespace std;

void one_proc(int iter)
{
    vector<double> vec(vec_size);
    vec[0] = vec[(vec_size /2)-1] = vec[vec_size - 1] = 1;
    for (int i = 0; i < iter; i++) {
        for (int j = 1; j < vec_size-1; j++)
        {
            if (j != vec_size/2-1) {
                    vec[j] = (vec[j - 1] + vec[j + 1]) / 2;
                }
        }
    }
    for (int i = 0; i < vec.size(); i++)
    {
        cout << vec[i] << " ";
    }
    cout << endl << endl;
}



int main(int argc, char **argv)
{
    int rank, size;

    vector <double> main_vector(vec_size);
    main_vector[0] = main_vector[(vec_size / 2)-1] = main_vector[vec_size - 1] = 1;
    MPI_Init(&argc, &argv);
    MPI_Comm_size(MPI_COMM_WORLD, &size);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);

    if (size == 1 || size==2)
    {
        one_proc(iter_num);
        MPI_Finalize();
        exit(0);
    }
    MPI_Request request;
    MPI_Status status;

    int proc_amount = size - 1;
    int temp_size = ((vec_size % proc_amount) ? (vec_size / proc_amount + 1) : (vec_size / proc_amount));
    vector<double> temp(temp_size);

    if (rank == 0)
    {
        for (int i = 1; i <= proc_amount; i++) {
            temp.assign(main_vector.begin() + (i - 1)*vec_size / proc_amount, main_vector.begin() + (i*vec_size / proc_amount));
            MPI_Isend(&temp[0], temp.size(), MPI_DOUBLE, i, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);
        }
    }
    else
    {
        temp[temp_size - 1] = -1;
        MPI_Irecv(&temp[0], temp_size, MPI_DOUBLE, 0, 0, MPI_COMM_WORLD, &request);
        MPI_Wait(&request, &status);
        if (temp[temp_size - 1] == -1)
        {
            temp.pop_back();
        }
    }


    double first, last;
    for (int i = 0; i < iter_num; i++)
    {
        if (rank == 1)
        {
            first = temp[temp.size() - 1];
            MPI_Isend(&first, 1, MPI_DOUBLE, 2, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);


            MPI_Irecv(&last, 1, MPI_DOUBLE, 2, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);
            temp.push_back(last);
            for (int j = 0; j < temp.size(); j++)
            {
                if (j != 0 && j != temp.size() - 1) {
                    if (temp[j] != 1) {
                        temp[j] = (temp[j - 1] + temp[j + 1]) / 2;
                    }
                }
            }
            temp.pop_back();
            first = temp[temp.size() - 1];

            cout << endl;
            for (int k = 0; k < temp.size(); k++) {
                cout << rank << " " << temp[k] << endl;
            }
        }
        else if (rank > 1 && rank < proc_amount)
        {
            last = temp[0];
            MPI_Isend(&last, 1, MPI_DOUBLE, rank - 1, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);

            MPI_Irecv(&first, 1, MPI_DOUBLE, rank - 1, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);

            temp.insert(temp.begin(), first);

            first = temp[temp.size() - 1];
            MPI_Isend(&first, 1, MPI_DOUBLE, rank + 1, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);


            MPI_Irecv(&last, 1, MPI_DOUBLE, rank + 1, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);

            temp.push_back(last);

            for (int j = 0; j < temp.size(); j++)
            {
                if (j != 0 && j != temp.size() - 1) {
                    if (temp[j] != 1) {
                        temp[j] = (temp[j - 1] + temp[j + 1]) / 2;
                    }
                }
            }


            temp.erase(temp.begin());
            temp.pop_back();

            cout << endl;
            for (int k = 0; k < temp.size(); k++) {
                cout << rank << " " << temp[k] << endl;
            }

        }
        else if (rank == proc_amount)
        {
            last = temp[0];
            MPI_Isend(&last, 1, MPI_DOUBLE, proc_amount - 1, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);

            MPI_Irecv(&first, 1, MPI_DOUBLE, proc_amount - 1, 0, MPI_COMM_WORLD, &request);
            MPI_Wait(&request, &status);

            temp.insert(temp.begin(), first);
            for (int j = 0; j < temp.size(); j++)
            {
                if (j != 0 && j != temp.size() - 1) {
                    if (temp[j] != 1) {
                        temp[j] = (temp[j - 1] + temp[j + 1]) / 2;
                    }
                }
            }
            temp.erase(temp.begin());
            cout << endl;
            for (int k = 0; k < temp.size(); k++) {
                cout << rank << " " << temp[k] << endl;
            }
        }

    }

    MPI_Finalize();

    system("pause");
    return 0;
}