#include <stdio.h>
#include <mpi.h>
 
int main(int argc, char** argv) {
    int rank, size;
    int send_data, recv_data;
 
    MPI_Init(&argc, &argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &size);
 
    if (size < 2) {
        printf("This example requires at least 2 processes.\n");
        MPI_Finalize();
        return 0;
    }
 
    if (rank == 0) {
        send_data = 42;
        MPI_Send(&send_data, 1, MPI_INT, 1, 0, MPI_COMM_WORLD);
        printf("Process %d sent data: %d\n", rank, send_data);
    } else if (rank == 1) {
        MPI_Recv(&recv_data, 1, MPI_INT, 0, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
        printf("Process %d received data: %d\n", rank, recv_data);
    }
 
    MPI_Finalize();
    return 0;
}
 

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