2015-09-18-4.c

#include <stdio.h>
#include <mpi.h>
#define W MPI_COMM_WORLD
#define n 4

void printArray(int size, int array[size], int rank) {
  for (int i = 0; i < size; i++) {
    if (rank == -1) printf("%02d ", array[i]);
    else printf("{%d}%02d ", rank, array[i]);
  }
  printf("\n");
}

void printMatrix(int rows, int cols, int matrix[rows][cols], int rank) {
  for (int i = 0; i < rows; i++) {
    printArray(cols, matrix[i], rank);
  }
}

int main(int argc, char** argv) {
  MPI_Init(&argc, &argv);
  int rank, size;
  MPI_Comm_rank(W, &rank);
  MPI_Comm_size(W, &size);

  int A[n][n], B[n][n] = {0};

  // Inicijalizacija
  if (rank == 0) {
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < n; j++) {
        A[i][j] = 10 * (i + 1) + j + 1;
      }
    }
  }

  // Nizovi [1, ..., n] i [n, ..., 1]
  // za duzine blokova matrica
  int bLensUpper[n], bLensLower[n];
  for (int i = 0; i < n; bLensLower[i++] = i);
  for (int i = 0; i < n; bLensUpper[i++] = n + 1 - i);

  // Nizovi za rastuci i opadajuci displacement
  int disUpper[n], disLower[n];
  for (int i = 0, j = 0; i < n; disLower[i++] = j++ * n);
  for (int i = 0, j = 0; i < n; disUpper[i++] = j++ * (n + 1));

  // Tipovi
  MPI_Datatype MPI_UPPER, MPI_LOWER;
  MPI_Type_indexed(n, bLensUpper, disUpper, MPI_INT, &MPI_UPPER);
  MPI_Type_indexed(n, bLensLower, disLower, MPI_INT, &MPI_LOWER);
  MPI_Type_commit(&MPI_UPPER);
  MPI_Type_commit(&MPI_LOWER);

  if (rank == 0) {
    MPI_Send(A, 1, MPI_UPPER, 1, 0, W);
  } else {
    MPI_Recv(B, 1, MPI_LOWER, 0, 0, W, MPI_STATUS_IGNORE);
  }

  if (rank == 0) {
    printf("\nA\n");
    printMatrix(n, n, A, -1);
  }
  MPI_Barrier(W);
  if (rank == 1) {
    printf("\nB\n");
    printMatrix(n, n, B, -1);
  }

  MPI_Finalize();
  return 0;
}