static char help[] = "Tests ISRenumber.\n\n";

#include <petscis.h>

PetscErrorCode TestRenumber(IS is, IS mult)
{
  IS       nis;
  PetscInt N;

  PetscFunctionBegin;
  PetscCall(PetscPrintf(PetscObjectComm((PetscObject)is),"\n-----------------\n"));
  PetscCall(PetscPrintf(PetscObjectComm((PetscObject)is),"\nInitial\n"));
  PetscCall(ISView(is,NULL));
  if (mult) {
    PetscCall(PetscPrintf(PetscObjectComm((PetscObject)is),"\nMult\n"));
    PetscCall(ISView(mult,NULL));
  }
  PetscCall(ISRenumber(is,mult,&N,NULL));
  PetscCall(PetscPrintf(PetscObjectComm((PetscObject)is),"\nRenumbered, unique entries %" PetscInt_FMT "\n",N));
  PetscCall(ISRenumber(is,mult,NULL,&nis));
  PetscCall(ISView(nis,NULL));
  PetscCall(ISDestroy(&nis));
  PetscFunctionReturn(0);
}

int main(int argc, char **argv)
{
  IS              is;
  PetscMPIInt     size, rank;

  PetscCall(PetscInitialize(&argc, &argv, NULL, help));
  PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
  PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));

  for (PetscInt c = 0; c < 3; c++) {
    IS mult = NULL;

    PetscCall(ISCreateStride(PETSC_COMM_WORLD,0,0,0,&is));
    if (c) {
      PetscInt n;
      PetscCall(ISGetLocalSize(is,&n));
      PetscCall(ISCreateStride(PETSC_COMM_WORLD,n,c-2,0,&mult));
    }
    PetscCall(TestRenumber(is,mult));
    PetscCall(ISDestroy(&is));
    PetscCall(ISDestroy(&mult));

    PetscCall(ISCreateStride(PETSC_COMM_WORLD,2,-rank-1,-4,&is));
    if (c) {
      PetscInt n;
      PetscCall(ISGetLocalSize(is,&n));
      PetscCall(ISCreateStride(PETSC_COMM_WORLD,n,c-2,0,&mult));
    }
    PetscCall(TestRenumber(is,mult));
    PetscCall(ISDestroy(&is));
    PetscCall(ISDestroy(&mult));

    PetscCall(ISCreateStride(PETSC_COMM_WORLD,10,4+rank,2,&is));
    if (c) {
      PetscInt n;
      PetscCall(ISGetLocalSize(is,&n));
      PetscCall(ISCreateStride(PETSC_COMM_WORLD,n,c-2,1,&mult));
    }
    PetscCall(TestRenumber(is,mult));
    PetscCall(ISDestroy(&is));
    PetscCall(ISDestroy(&mult));

    PetscCall(ISCreateStride(PETSC_COMM_WORLD,10,-rank-1,2,&is));
    if (c) {
      PetscInt n;
      PetscCall(ISGetLocalSize(is,&n));
      PetscCall(ISCreateStride(PETSC_COMM_WORLD,n,c-2,1,&mult));
    }
    PetscCall(TestRenumber(is,mult));
    PetscCall(ISDestroy(&is));
    PetscCall(ISDestroy(&mult));
  }
  /* Finalize */
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

  test:
    suffix: 1
    nsize: {{1 2}separate output}

TEST*/