#include <mpi.h>
#include <stdio.h>
#include <iostream>

int main(int argc, char** argv) {
    srand(time(0));
    int size;
    int *arr = nullptr, *vec = nullptr, *localArr = nullptr, *localArr2 = nullptr, *arrSums = nullptr;
    MPI_Init(&argc,  &argv);
    int world_size;
    MPI_Comm_size(MPI_COMM_WORLD, &world_size);
    int world_rank;
    MPI_Comm_rank(MPI_COMM_WORLD, &world_rank);
    if(world_rank == 0) {
        std::cout<< "Size: ";
        std::cin >> size;
        arr = new int[size*size];
        for(int i=0; i<size; i++) {
            for(int j=0; j<size; j++) {
                arr[i*size + j] = rand()%10;
                std::cout << arr[i*size + j] << " ";
            }
            std::cout << std::endl;
        }
        std::cout << std::endl;
        vec = new int[size];
        for(int i=0; i<size; i++) {
            vec[i] = rand()%10;
            std::cout << vec[i] << " ";
        }
        std::cout << std::endl;
        arrSums = new int[size];
    }

    MPI_Bcast(&size, 1, MPI_INT, 0, MPI_COMM_WORLD);
    std::cout << world_rank << ": " << size <<std::endl;
    MPI_Bcast(vec, size, MPI_INT, 0, MPI_COMM_WORLD);
    /*for(int i=0; i<size; i++) {
            std::cout << vec[i] << " ";
    }
    std::cout << std::endl;
        /*
    int countVar = (size * size) / world_size;
    localArr = new int[countVar];

    MPI_Scatter(arr, countVar, MPI_INT, localArr, countVar, MPI_INT, 0, MPI_COMM_WORLD);
    int sum(0);
    for (int i=0; i<countVar; i++) {
        sum += localArr[i] * vec[i%size];
    }
    MPI_Gather(&sum, 1, MPI_INT, arrSums, 1, MPI_INT, 0, MPI_COMM_WORLD);
    if(world_rank == 0) {
        for(int i=0; i<size; i++) {
            std::cout << arrSums[i] << " ";
        }
    }*/
    MPI_Finalize();
}