static char help[] = "Tests MatMPIAIJSetPreallocationCSR()\n\n";

/*
  Include "petscmat.h" so that we can use matrices.  Note that this file
  automatically includes:
     petscsys.h       - base PETSc routines   petscvec.h - vectors
     petscmat.h - matrices
     petscis.h     - index sets
     petscviewer.h - viewers
*/
#include <petscmat.h>

int main(int argc,char **args)
{
  Mat            A;
  PetscInt       *ia,*ja;
  PetscMPIInt    rank,size;

  PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
  PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
  PetscCheck(size == 4,PETSC_COMM_WORLD,PETSC_ERR_WRONG_MPI_SIZE,"Must run with 4 processors");
  PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));

  PetscCall(PetscMalloc1(5,&ia));
  PetscCall(PetscMalloc1(16,&ja));
  if (rank == 0) {
    ja[0] = 1; ja[1] = 4; ja[2] = 0; ja[3] = 2; ja[4] = 5; ja[5] = 1; ja[6] = 3; ja[7] = 6;
    ja[8] = 2; ja[9] = 7;
    ia[0] = 0; ia[1] = 2; ia[2] = 5; ia[3] = 8; ia[4] = 10;
  } else if (rank == 1) {
    ja[0] = 0; ja[1] = 5; ja[2] = 8; ja[3] = 1; ja[4] = 4; ja[5] = 6; ja[6] = 9; ja[7] = 2;
    ja[8] = 5; ja[9] = 7; ja[10] = 10; ja[11] = 3; ja[12] = 6; ja[13] = 11;
    ia[0] = 0; ia[1] = 3; ia[2] = 7; ia[3] = 11; ia[4] = 14;
  } else if (rank == 2) {
    ja[0] = 4; ja[1] = 9; ja[2] = 12; ja[3] = 5; ja[4] = 8; ja[5] = 10; ja[6] = 13; ja[7] = 6;
    ja[8] = 9; ja[9] = 11; ja[10] = 14; ja[11] = 7; ja[12] = 10; ja[13] = 15;
    ia[0] = 0; ia[1] = 3; ia[2] = 7; ia[3] = 11; ia[4] = 14;
  } else {
    ja[0] = 8; ja[1] = 13; ja[2] = 9; ja[3] = 12; ja[4] = 14; ja[5] = 10; ja[6] = 13; ja[7] = 15;
    ja[8] = 11; ja[9] = 14;
    ia[0] = 0; ia[1] = 2; ia[2] = 5; ia[3] = 8; ia[4] = 10;
  }

  PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
  PetscCall(MatSetSizes(A,4,4,16,16));
  PetscCall(MatSetType(A,MATMPIAIJ));
  PetscCall(MatMPIAIJSetPreallocationCSR(A,ia,ja,NULL));
  PetscCall(PetscFree(ia));
  PetscCall(PetscFree(ja));
  PetscCall(MatView(A,PETSC_VIEWER_STDOUT_WORLD));
  PetscCall(MatDestroy(&A));
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   test:
      nsize: 4

TEST*/