printf("%d ", sb[i]);
printf("]\n");
status = MPI_Allgather(sb, count, MPI_INT, rb, count, MPI_INT, MPI_COMM_WORLD);
printf("[%d] rcvbuf=[", rank);
printf("%d ", sb[i]);
printf("]\n");
status = MPI_Allgather(sb, count, MPI_INT, rb, count, MPI_INT, MPI_COMM_WORLD);
printf("[%d] rcvbuf=[", rank);