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

#include <petscsys.h>
#include <petscviewer.h>

int main(int argc,char **args)
{
  PetscErrorCode ierr;
  PetscHeap      h;
  PetscInt       id,val,cnt,*values;

  ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
  ierr = PetscHeapCreate(9,&h);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,0,100);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,1,19);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,2,36);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,3,17);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,4,3);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,5,25);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,6,1);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,8,2);CHKERRQ(ierr);
  ierr = PetscHeapAdd(h,9,7);CHKERRQ(ierr);
  ierr = PetscPrintf(PETSC_COMM_SELF,"Initial heap:\n");CHKERRQ(ierr);
  ierr = PetscHeapView(h,NULL);CHKERRQ(ierr);

  ierr = PetscHeapPop(h,&id,&val);CHKERRQ(ierr);
  ierr = PetscHeapStash(h,id,val+10);CHKERRQ(ierr);
  ierr = PetscHeapPop(h,&id,&val);CHKERRQ(ierr);
  ierr = PetscHeapStash(h,id,val+10);CHKERRQ(ierr);
  ierr = PetscPrintf(PETSC_COMM_SELF,"Pop two items, increment, and place in stash:\n");CHKERRQ(ierr);
  ierr = PetscHeapView(h,NULL);CHKERRQ(ierr);

  ierr = PetscHeapUnstash(h);CHKERRQ(ierr);
  ierr = PetscPrintf(PETSC_COMM_SELF,"After unpacking the stash:\n");CHKERRQ(ierr);
  ierr = PetscHeapView(h,NULL);CHKERRQ(ierr);

  ierr = PetscMalloc1(9,&values);CHKERRQ(ierr);
  ierr = PetscHeapPop(h,&id,&val);CHKERRQ(ierr);
  cnt  = 0;
  while (id >= 0) {
    values[cnt++] = val;
    ierr          = PetscHeapPop(h,&id,&val);CHKERRQ(ierr);
  }
  ierr = PetscPrintf(PETSC_COMM_SELF,"Sorted values:\n");CHKERRQ(ierr);
  ierr = PetscIntView(cnt,values,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);
  ierr = PetscFree(values);CHKERRQ(ierr);
  ierr = PetscHeapDestroy(&h);CHKERRQ(ierr);
  ierr = PetscFinalize();
  return ierr;
}

/*TEST

   test:

TEST*/