static const char help[] = "Test VecScatterCopy() on an SF with duplicated leaves \n\n";

#include <petscvec.h>
#include <petscsf.h>

/*
  Contributed-by: "Hammond, Glenn E" <glenn.hammond@pnnl.gov>
*/
int main(int argc, char *argv[])
{
  PetscMPIInt size;
  PetscInt    n;
  PetscInt   *indices;
  Vec         vec;
  Vec         vec2;
  IS          is;
  IS          is2;
  VecScatter  scatter;
  VecScatter  scatter2;

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &argv, NULL, help));
  PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
  PetscCheck(size == 1, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "This example requires 1 process");

  n = 4;
  PetscCall(PetscMalloc1(n, &indices));
  indices[0] = 0;
  indices[1] = 1;
  indices[2] = 2;
  indices[3] = 3;
  PetscCall(ISCreateGeneral(PETSC_COMM_WORLD, n, indices, PETSC_COPY_VALUES, &is));
  PetscCall(PetscFree(indices));
  PetscCall(VecCreateFromOptions(PETSC_COMM_WORLD, NULL, 1, n, n, &vec));

  n = 4;
  PetscCall(PetscMalloc1(n, &indices));
  indices[0] = 0;
  indices[1] = 0;
  indices[2] = 1;
  indices[3] = 1;
  PetscCall(ISCreateGeneral(PETSC_COMM_WORLD, n, indices, PETSC_COPY_VALUES, &is2));
  PetscCall(PetscFree(indices));
  PetscCall(VecCreateFromOptions(PETSC_COMM_WORLD, NULL, 1, n / 2, n / 2, &vec2));

  PetscCall(VecScatterCreate(vec, is, vec2, is2, &scatter));
  PetscCall(ISDestroy(&is));
  PetscCall(ISDestroy(&is2));

  PetscCall(VecScatterCopy(scatter, &scatter2));

  PetscCall(VecDestroy(&vec));
  PetscCall(VecDestroy(&vec2));
  PetscCall(VecScatterDestroy(&scatter));
  PetscCall(VecScatterDestroy(&scatter2));
  PetscCall(PetscFinalize());
}

/*TEST
  test:
    nsize: 1
    output_file: output/empty.out
TEST*/