!!$ 
!!$              Parallel Sparse BLAS  version 3.4
!!$    (C) Copyright 2006, 2010, 2015
!!$                       Salvatore Filippone    University of Rome Tor Vergata
!!$                       Alfredo Buttari        CNRS-IRIT, Toulouse
!!$ 
!!$  Redistribution and use in source and binary forms, with or without
!!$  modification, are permitted provided that the following conditions
!!$  are met:
!!$    1. Redistributions of source code must retain the above copyright
!!$       notice, this list of conditions and the following disclaimer.
!!$    2. Redistributions in binary form must reproduce the above copyright
!!$       notice, this list of conditions, and the following disclaimer in the
!!$       documentation and/or other materials provided with the distribution.
!!$    3. The name of the PSBLAS group or the names of its contributors may
!!$       not be used to endorse or promote products derived from this
!!$       software without specific written permission.
!!$ 
!!$  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
!!$  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
!!$  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
!!$  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS
!!$  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
!!$  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
!!$  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
!!$  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
!!$  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
!!$  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
!!$  POSSIBILITY OF SUCH DAMAGE.
!!$ 
!!$  
!
!  The merge-sort and quicksort routines are implemented in the
!  serial/aux directory
!  References:
!  D. Knuth
!  The Art of Computer Programming, vol. 3
!  Addison-Wesley
!  
!  Aho, Hopcroft, Ullman
!  Data Structures and Algorithms
!  Addison-Wesley
!

module psb_sort_mod
  use psb_const_mod
  use psb_ip_reord_mod
  use psb_i_sort_mod
  use psb_s_sort_mod
  use psb_c_sort_mod
  use psb_d_sort_mod
  use psb_z_sort_mod

!!$module psb_sort_mod
!!$  use psb_const_mod
!!$
!!$
!!$  type psb_int_heap
!!$    integer(psb_ipk_) :: last, dir
!!$    integer(psb_ipk_), allocatable :: keys(:)
!!$  end type psb_int_heap
!!$  type psb_int_idx_heap
!!$    integer(psb_ipk_) :: last, dir
!!$    integer(psb_ipk_), allocatable :: keys(:)
!!$    integer(psb_ipk_), allocatable :: idxs(:)
!!$  end type psb_int_idx_heap
!!$  type psb_sreal_idx_heap
!!$    integer(psb_ipk_) :: last, dir
!!$    real(psb_spk_), allocatable    :: keys(:)
!!$    integer(psb_ipk_), allocatable :: idxs(:)
!!$  end type psb_sreal_idx_heap
!!$  type psb_dreal_idx_heap
!!$    integer(psb_ipk_) :: last, dir
!!$    real(psb_dpk_), allocatable    :: keys(:)
!!$    integer(psb_ipk_), allocatable :: idxs(:)
!!$  end type psb_dreal_idx_heap
!!$  type psb_scomplex_idx_heap
!!$    integer(psb_ipk_) :: last, dir
!!$    complex(psb_spk_), allocatable :: keys(:)
!!$    integer(psb_ipk_), allocatable :: idxs(:)
!!$  end type psb_scomplex_idx_heap
!!$  type psb_dcomplex_idx_heap
!!$    integer(psb_ipk_) :: last, dir
!!$    complex(psb_dpk_), allocatable :: keys(:)
!!$    integer(psb_ipk_), allocatable :: idxs(:)
!!$  end type psb_dcomplex_idx_heap
!!$
!!$
!!$  interface psb_iblsrch
!!$    function  psb_iblsrch(key,n,v) result(ipos)
!!$      import :: psb_ipk_
!!$      integer(psb_ipk_) :: ipos, key, n
!!$      integer(psb_ipk_) :: v(:)
!!$    end function psb_iblsrch
!!$  end interface
!!$
!!$  interface psb_ibsrch
!!$    function  psb_ibsrch(key,n,v) result(ipos)
!!$      import :: psb_ipk_
!!$      integer(psb_ipk_) :: ipos, key, n
!!$      integer(psb_ipk_) :: v(:)
!!$    end function psb_ibsrch
!!$  end interface
!!$
!!$  interface psb_issrch
!!$    function psb_issrch(key,n,v) result(ipos)
!!$      import :: psb_ipk_
!!$      implicit none
!!$      integer(psb_ipk_) :: ipos, key, n
!!$      integer(psb_ipk_) :: v(:)
!!$    end function psb_issrch
!!$  end interface
!!$
!!$  interface psb_isaperm
!!$    logical function psb_isaperm(n,eip)               
!!$      import :: psb_ipk_
!!$      integer(psb_ipk_), intent(in) :: n                             
!!$      integer(psb_ipk_), intent(in) :: eip(n)
!!$    end function psb_isaperm
!!$  end interface
!!$
!!$
!!$  interface psb_msort
!!$    subroutine imsort(x,ix,dir,flag)
!!$      import :: psb_ipk_
!!$      integer(psb_ipk_), intent(inout)           :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine imsort
!!$    subroutine smsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      real(psb_spk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine smsort
!!$    subroutine dmsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      real(psb_dpk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine dmsort
!!$    subroutine camsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      complex(psb_spk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine camsort
!!$    subroutine zamsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      complex(psb_dpk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine zamsort
!!$  end interface
!!$
!!$
!!$  interface psb_msort_unique
!!$    subroutine imsort_u(x,nout,dir)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      integer(psb_ipk_), intent(inout)           :: x(:) 
!!$      integer(psb_ipk_), intent(out)             :: nout
!!$      integer(psb_ipk_), optional, intent(in)    :: dir
!!$    end subroutine imsort_u
!!$  end interface
!!$
!!$  interface psb_qsort
!!$    subroutine iqsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      integer(psb_ipk_), intent(inout)           :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine iqsort
!!$    subroutine sqsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      real(psb_spk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine sqsort
!!$    subroutine dqsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      real(psb_dpk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine dqsort
!!$    subroutine cqsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      complex(psb_spk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine cqsort
!!$    subroutine zqsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      complex(psb_dpk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine zqsort
!!$  end interface
!!$  
!!$
!!$  interface psb_hsort
!!$    subroutine ihsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      integer(psb_ipk_), intent(inout)           :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine ihsort
!!$    subroutine shsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      real(psb_spk_), intent(inout)    :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine shsort
!!$    subroutine dhsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      real(psb_dpk_), intent(inout)  :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine dhsort
!!$    subroutine chsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      complex(psb_spk_), intent(inout) :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)    :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout) :: ix(:)
!!$    end subroutine chsort
!!$    subroutine zhsort(x,ix,dir,flag)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      complex(psb_dpk_), intent(inout) :: x(:) 
!!$      integer(psb_ipk_), optional, intent(in)      :: dir, flag
!!$      integer(psb_ipk_), optional, intent(inout)   :: ix(:)
!!$    end subroutine zhsort
!!$  end interface
!!$
!!$
!!$  interface psb_howmany_heap
!!$    function  psb_howmany_int_heap(heap)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_int_heap
!!$      type(psb_int_heap), intent(in) :: heap
!!$      integer(psb_ipk_) :: psb_howmany_int_heap
!!$    end function psb_howmany_int_heap
!!$    function  psb_howmany_sreal_idx_heap(heap)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_sreal_idx_heap
!!$      type(psb_sreal_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_) :: psb_howmany_sreal_idx_heap
!!$    end function psb_howmany_sreal_idx_heap
!!$    function  psb_howmany_dreal_idx_heap(heap)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_dreal_idx_heap
!!$      type(psb_dreal_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_) :: psb_howmany_dreal_idx_heap
!!$    end function psb_howmany_dreal_idx_heap
!!$    function  psb_howmany_int_idx_heap(heap)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_int_idx_heap
!!$      type(psb_int_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_) :: psb_howmany_int_idx_heap
!!$    end function psb_howmany_int_idx_heap
!!$    function  psb_howmany_scomplex_idx_heap(heap)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_scomplex_idx_heap
!!$      type(psb_scomplex_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_) :: psb_howmany_scomplex_idx_heap
!!$    end function psb_howmany_scomplex_idx_heap
!!$    function  psb_howmany_dcomplex_idx_heap(heap)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_dcomplex_idx_heap
!!$      type(psb_dcomplex_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_) :: psb_howmany_dcomplex_idx_heap
!!$    end function psb_howmany_dcomplex_idx_heap
!!$  end interface
!!$ 
!!$
!!$  interface psb_init_heap
!!$    subroutine psb_init_int_heap(heap,info,dir)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_int_heap
!!$      type(psb_int_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)            :: info
!!$      integer(psb_ipk_), intent(in), optional   :: dir
!!$    end subroutine psb_init_int_heap
!!$    subroutine psb_init_sreal_idx_heap(heap,info,dir)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_sreal_idx_heap
!!$      type(psb_sreal_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)            :: info
!!$      integer(psb_ipk_), intent(in), optional   :: dir
!!$    end subroutine psb_init_sreal_idx_heap
!!$    subroutine psb_init_int_idx_heap(heap,info,dir)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_int_idx_heap
!!$      type(psb_int_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)            :: info
!!$      integer(psb_ipk_), intent(in), optional   :: dir
!!$    end subroutine psb_init_int_idx_heap
!!$    subroutine psb_init_scomplex_idx_heap(heap,info,dir)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_scomplex_idx_heap
!!$      type(psb_scomplex_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)            :: info
!!$      integer(psb_ipk_), intent(in), optional   :: dir
!!$    end subroutine psb_init_scomplex_idx_heap
!!$    subroutine psb_init_dcomplex_idx_heap(heap,info,dir)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_dcomplex_idx_heap
!!$      type(psb_dcomplex_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)            :: info
!!$      integer(psb_ipk_), intent(in), optional   :: dir
!!$    end subroutine psb_init_dcomplex_idx_heap
!!$    subroutine psb_init_dreal_idx_heap(heap,info,dir)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_dreal_idx_heap
!!$      type(psb_dreal_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)            :: info
!!$      integer(psb_ipk_), intent(in), optional   :: dir
!!$    end subroutine psb_init_dreal_idx_heap
!!$  end interface
!!$
!!$
!!$  interface psb_dump_heap
!!$    subroutine psb_dump_int_heap(iout,heap,info)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_int_heap
!!$      type(psb_int_heap), intent(in) :: heap
!!$      integer(psb_ipk_), intent(out)           :: info
!!$      integer(psb_ipk_), intent(in)            :: iout
!!$    end subroutine psb_dump_int_heap
!!$    subroutine psb_dump_sreal_idx_heap(iout,heap,info)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_sreal_idx_heap
!!$      type(psb_sreal_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_), intent(out)           :: info
!!$      integer(psb_ipk_), intent(in)            :: iout
!!$    end subroutine psb_dump_sreal_idx_heap
!!$    subroutine psb_dump_dreal_idx_heap(iout,heap,info)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_dreal_idx_heap
!!$      type(psb_dreal_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_), intent(out)           :: info
!!$      integer(psb_ipk_), intent(in)            :: iout
!!$    end subroutine psb_dump_dreal_idx_heap
!!$    subroutine psb_dump_int_idx_heap(iout,heap,info)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_int_idx_heap
!!$      type(psb_int_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_), intent(out)           :: info
!!$      integer(psb_ipk_), intent(in)            :: iout
!!$    end subroutine psb_dump_int_idx_heap
!!$    subroutine psb_dump_scomplex_idx_heap(iout,heap,info)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_scomplex_idx_heap
!!$      type(psb_scomplex_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_), intent(out)           :: info
!!$      integer(psb_ipk_), intent(in)            :: iout
!!$    end subroutine psb_dump_scomplex_idx_heap
!!$    subroutine psb_dump_dcomplex_idx_heap(iout,heap,info)
!!$      import :: psb_ipk_, psb_spk_, psb_dpk_
!!$      import :: psb_dcomplex_idx_heap
!!$      type(psb_dcomplex_idx_heap), intent(in) :: heap
!!$      integer(psb_ipk_), intent(out)           :: info
!!$      integer(psb_ipk_), intent(in)            :: iout
!!$    end subroutine psb_dump_dcomplex_idx_heap
!!$  end interface
!!$
!!$
!!$  interface psb_insert_heap
!!$    subroutine psb_insert_int_heap(key,heap,info)
!!$      import :: psb_int_heap, psb_ipk_
!!$      integer(psb_ipk_), intent(in)               :: key
!!$      type(psb_int_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)              :: info
!!$    end subroutine psb_insert_int_heap
!!$    subroutine psb_insert_int_idx_heap(key,index,heap,info)
!!$      import :: psb_dpk_, psb_int_idx_heap, psb_ipk_
!!$      integer(psb_ipk_), intent(in)                   :: key
!!$      integer(psb_ipk_), intent(in)                   :: index
!!$      type(psb_int_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)                  :: info
!!$    end subroutine psb_insert_int_idx_heap
!!$    subroutine psb_insert_sreal_idx_heap(key,index,heap,info)
!!$      import :: psb_spk_, psb_sreal_idx_heap, psb_ipk_
!!$      real(psb_spk_), intent(in)      :: key
!!$      integer(psb_ipk_), intent(in)               :: index
!!$      type(psb_sreal_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)              :: info
!!$    end subroutine psb_insert_sreal_idx_heap
!!$    subroutine psb_insert_dreal_idx_heap(key,index,heap,info)
!!$      import :: psb_dpk_, psb_dreal_idx_heap, psb_ipk_
!!$      real(psb_dpk_), intent(in)      :: key
!!$      integer(psb_ipk_), intent(in)               :: index
!!$      type(psb_dreal_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)              :: info
!!$    end subroutine psb_insert_dreal_idx_heap
!!$    subroutine psb_insert_scomplex_idx_heap(key,index,heap,info)
!!$      import :: psb_spk_, psb_scomplex_idx_heap, psb_ipk_
!!$      complex(psb_spk_), intent(in)              :: key
!!$      integer(psb_ipk_), intent(in)                        :: index
!!$      type(psb_scomplex_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)                       :: info
!!$    end subroutine psb_insert_scomplex_idx_heap
!!$    subroutine psb_insert_dcomplex_idx_heap(key,index,heap,info)
!!$      import :: psb_dpk_, psb_dcomplex_idx_heap, psb_ipk_
!!$      complex(psb_dpk_), intent(in)            :: key
!!$      integer(psb_ipk_), intent(in)                        :: index
!!$      type(psb_dcomplex_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)                       :: info
!!$    end subroutine psb_insert_dcomplex_idx_heap
!!$  end interface
!!$
!!$  interface psb_heap_get_first
!!$    subroutine psb_int_heap_get_first(key,heap,info)
!!$      import :: psb_int_heap, psb_ipk_
!!$      type(psb_int_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)              :: key,info
!!$    end subroutine psb_int_heap_get_first
!!$    subroutine psb_int_idx_heap_get_first(key,index,heap,info)
!!$      import :: psb_int_idx_heap, psb_ipk_
!!$      type(psb_int_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)                  :: index,info
!!$      integer(psb_ipk_), intent(out)                  :: key
!!$    end subroutine psb_int_idx_heap_get_first
!!$    subroutine psb_sreal_idx_heap_get_first(key,index,heap,info)
!!$      import :: psb_spk_, psb_sreal_idx_heap, psb_ipk_
!!$      type(psb_sreal_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)              :: index,info
!!$      real(psb_spk_), intent(out)     :: key
!!$    end subroutine psb_sreal_idx_heap_get_first
!!$    subroutine psb_dreal_idx_heap_get_first(key,index,heap,info)
!!$      import :: psb_dpk_, psb_dreal_idx_heap, psb_ipk_
!!$      type(psb_dreal_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)              :: index,info
!!$      real(psb_dpk_), intent(out)     :: key
!!$    end subroutine psb_dreal_idx_heap_get_first
!!$    subroutine psb_scomplex_idx_heap_get_first(key,index,heap,info)
!!$      import :: psb_spk_, psb_scomplex_idx_heap, psb_ipk_
!!$      type(psb_scomplex_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)                       :: index,info
!!$      complex(psb_spk_), intent(out)           :: key
!!$    end subroutine psb_scomplex_idx_heap_get_first
!!$    
!!$    subroutine psb_dcomplex_idx_heap_get_first(key,index,heap,info)
!!$      import :: psb_dpk_, psb_dcomplex_idx_heap, psb_ipk_
!!$      type(psb_dcomplex_idx_heap), intent(inout) :: heap
!!$      integer(psb_ipk_), intent(out)                       :: index,info
!!$      complex(psb_dpk_), intent(out)           :: key
!!$    end subroutine psb_dcomplex_idx_heap_get_first
!!$  end interface
!!$
!!$  interface 
!!$    subroutine psi_insert_int_heap(key,last,heap,dir,info)
!!$      import :: psb_ipk_
!!$      implicit none 
!!$      
!!$      !  
!!$      ! Input: 
!!$      !   key:  the new value
!!$      !   last: pointer to the last occupied element in heap
!!$      !   heap: the heap
!!$      !   dir:  sorting direction
!!$      
!!$      integer(psb_ipk_), intent(in)     :: key,dir
!!$      integer(psb_ipk_), intent(inout)  :: heap(:),last
!!$      integer(psb_ipk_), intent(out)    :: info
!!$    end subroutine psi_insert_int_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_int_heap_get_first(key,last,heap,dir,info)
!!$      import :: psb_ipk_
!!$      implicit none 
!!$     
!!$      integer(psb_ipk_), intent(inout)  :: key,last
!!$      integer(psb_ipk_), intent(in)     :: dir
!!$      integer(psb_ipk_), intent(inout)  :: heap(:)
!!$      integer(psb_ipk_), intent(out)    :: info
!!$    end subroutine psi_int_heap_get_first
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_insert_real_heap(key,last,heap,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      real(psb_spk_), intent(in)    :: key
!!$      integer(psb_ipk_), intent(in)           :: dir
!!$      real(psb_spk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(inout)        :: last
!!$      integer(psb_ipk_), intent(out)          :: info
!!$    end subroutine psi_insert_real_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_real_heap_get_first(key,last,heap,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      real(psb_spk_), intent(inout) :: key
!!$      integer(psb_ipk_), intent(inout)        :: last
!!$      integer(psb_ipk_), intent(in)           :: dir
!!$      real(psb_spk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)          :: info
!!$    end subroutine psi_real_heap_get_first
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_insert_double_heap(key,last,heap,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      real(psb_dpk_), intent(in)    :: key
!!$      integer(psb_ipk_), intent(in)             :: dir
!!$      real(psb_dpk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(inout)          :: last
!!$      integer(psb_ipk_), intent(out)            :: info
!!$    end subroutine psi_insert_double_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_double_heap_get_first(key,last,heap,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      real(psb_dpk_), intent(inout) :: key
!!$      integer(psb_ipk_), intent(inout)          :: last
!!$      integer(psb_ipk_), intent(in)             :: dir
!!$      real(psb_dpk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)            :: info
!!$    end subroutine psi_double_heap_get_first
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_insert_scomplex_heap(key,last,heap,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      complex(psb_spk_), intent(in)    :: key
!!$      integer(psb_ipk_), intent(in)              :: dir
!!$      complex(psb_spk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(inout)           :: last
!!$      integer(psb_ipk_), intent(out)             :: info
!!$    end subroutine psi_insert_scomplex_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_scomplex_heap_get_first(key,last,heap,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      complex(psb_spk_), intent(inout) :: key
!!$      integer(psb_ipk_), intent(inout)           :: last
!!$      integer(psb_ipk_), intent(in)              :: dir
!!$      complex(psb_spk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)             :: info
!!$    end subroutine psi_scomplex_heap_get_first
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_insert_dcomplex_heap(key,last,heap,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      complex(psb_dpk_), intent(in)    :: key
!!$      integer(psb_ipk_), intent(in)                :: dir
!!$      complex(psb_dpk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(inout)             :: last
!!$      integer(psb_ipk_), intent(out)               :: info
!!$    end subroutine psi_insert_dcomplex_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_dcomplex_heap_get_first(key,last,heap,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      complex(psb_dpk_), intent(inout) :: key
!!$      integer(psb_ipk_), intent(inout)             :: last
!!$      integer(psb_ipk_), intent(in)                :: dir
!!$      complex(psb_dpk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)               :: info
!!$    end subroutine psi_dcomplex_heap_get_first
!!$  end interface
!!$
!!$  interface 
!!$    subroutine psi_insert_int_idx_heap(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_ipk_
!!$      integer(psb_ipk_), intent(in)     :: key
!!$      integer(psb_ipk_), intent(in)     :: index,dir
!!$      integer(psb_ipk_), intent(inout)  :: heap(:),last
!!$      integer(psb_ipk_), intent(inout)  :: idxs(:)
!!$      integer(psb_ipk_), intent(out)    :: info
!!$    end subroutine psi_insert_int_idx_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_int_idx_heap_get_first(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_ipk_
!!$      integer(psb_ipk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)   :: index,info
!!$      integer(psb_ipk_), intent(inout) :: last,idxs(:)
!!$      integer(psb_ipk_), intent(in)    :: dir
!!$      integer(psb_ipk_), intent(out)   :: key
!!$    end subroutine psi_int_idx_heap_get_first
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_insert_sreal_idx_heap(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      real(psb_spk_), intent(in)     :: key
!!$      integer(psb_ipk_), intent(in)            :: index,dir
!!$      real(psb_spk_), intent(inout)  :: heap(:)
!!$      integer(psb_ipk_), intent(inout)         :: idxs(:),last
!!$      integer(psb_ipk_), intent(out)           :: info
!!$    end subroutine psi_insert_sreal_idx_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_sreal_idx_heap_get_first(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      real(psb_spk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)          :: index,info
!!$      integer(psb_ipk_), intent(inout)        :: last,idxs(:)
!!$      integer(psb_ipk_), intent(in)           :: dir
!!$      real(psb_spk_), intent(out)   :: key
!!$    end subroutine psi_sreal_idx_heap_get_first
!!$  end interface
!!$
!!$  interface 
!!$    subroutine psi_insert_dreal_idx_heap(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      real(psb_dpk_), intent(in)     :: key
!!$      integer(psb_ipk_), intent(in)              :: index,dir
!!$      real(psb_dpk_), intent(inout)  :: heap(:)
!!$      integer(psb_ipk_), intent(inout)           :: idxs(:),last
!!$      integer(psb_ipk_), intent(out)             :: info
!!$    end subroutine psi_insert_dreal_idx_heap
!!$  end interface
!!$  
!!$  interface 
!!$    subroutine psi_dreal_idx_heap_get_first(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      real(psb_dpk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)            :: index,info
!!$      integer(psb_ipk_), intent(inout)          :: last,idxs(:)
!!$      integer(psb_ipk_), intent(in)             :: dir
!!$      real(psb_dpk_), intent(out)   :: key
!!$    end subroutine psi_dreal_idx_heap_get_first
!!$  end interface
!!$
!!$  interface 
!!$    subroutine psi_insert_scomplex_idx_heap(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      complex(psb_spk_), intent(in)    :: key
!!$      integer(psb_ipk_), intent(in)              :: index,dir
!!$      complex(psb_spk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(inout)           :: idxs(:),last
!!$      integer(psb_ipk_), intent(out)             :: info
!!$    end subroutine psi_insert_scomplex_idx_heap
!!$  end interface
!!$
!!$  interface 
!!$    subroutine psi_scomplex_idx_heap_get_first(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_spk_, psb_ipk_
!!$      complex(psb_spk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)             :: index,info
!!$      integer(psb_ipk_), intent(inout)           :: last,idxs(:)
!!$      integer(psb_ipk_), intent(in)              :: dir
!!$      complex(psb_spk_), intent(out)   :: key
!!$    end subroutine psi_scomplex_idx_heap_get_first
!!$  end interface
!!$
!!$  interface 
!!$    subroutine psi_insert_dcomplex_idx_heap(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      complex(psb_dpk_), intent(in)    :: key
!!$      integer(psb_ipk_), intent(in)                :: index,dir
!!$      complex(psb_dpk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(inout)             :: idxs(:),last
!!$      integer(psb_ipk_), intent(out)               :: info
!!$    end subroutine psi_insert_dcomplex_idx_heap
!!$  end interface
!!$
!!$  interface 
!!$    subroutine psi_dcomplex_idx_heap_get_first(key,index,last,heap,idxs,dir,info)
!!$      import :: psb_dpk_, psb_ipk_
!!$      complex(psb_dpk_), intent(inout) :: heap(:)
!!$      integer(psb_ipk_), intent(out)               :: index,info
!!$      integer(psb_ipk_), intent(inout)             :: last,idxs(:)
!!$      integer(psb_ipk_), intent(in)                :: dir
!!$      complex(psb_dpk_), intent(out)   :: key
!!$    end subroutine psi_dcomplex_idx_heap_get_first
!!$  end interface
!!$  
!!$
!!$  interface psb_free_heap
!!$    module procedure psb_free_int_heap, psb_free_int_idx_heap,&
!!$         & psb_free_sreal_idx_heap, psb_free_scomplex_idx_heap, &
!!$         & psb_free_dreal_idx_heap, psb_free_dcomplex_idx_heap
!!$  end interface
!!$
!!$contains
!!$
!!$  subroutine psb_free_int_heap(heap,info)
!!$    implicit none 
!!$    type(psb_int_heap), intent(inout) :: heap
!!$    integer(psb_ipk_), intent(out)           :: info
!!$
!!$    info=psb_success_
!!$    if (allocated(heap%keys)) deallocate(heap%keys,stat=info)
!!$
!!$  end subroutine psb_free_int_heap
!!$
!!$  subroutine psb_free_sreal_idx_heap(heap,info)
!!$    implicit none 
!!$    type(psb_sreal_idx_heap), intent(inout) :: heap
!!$    integer(psb_ipk_), intent(out)           :: info
!!$
!!$    info=psb_success_
!!$    if (allocated(heap%keys)) deallocate(heap%keys,stat=info)
!!$    if ((info == psb_success_).and.(allocated(heap%idxs))) deallocate(heap%idxs,stat=info)
!!$
!!$  end subroutine psb_free_sreal_idx_heap
!!$
!!$  subroutine psb_free_dreal_idx_heap(heap,info)
!!$    implicit none 
!!$    type(psb_dreal_idx_heap), intent(inout) :: heap
!!$    integer(psb_ipk_), intent(out)           :: info
!!$
!!$    info=psb_success_
!!$    if (allocated(heap%keys)) deallocate(heap%keys,stat=info)
!!$    if ((info == psb_success_).and.(allocated(heap%idxs))) deallocate(heap%idxs,stat=info)
!!$
!!$  end subroutine psb_free_dreal_idx_heap
!!$
!!$  subroutine psb_free_int_idx_heap(heap,info)
!!$    implicit none 
!!$    type(psb_int_idx_heap), intent(inout) :: heap
!!$    integer(psb_ipk_), intent(out)           :: info
!!$
!!$    info=psb_success_
!!$    if (allocated(heap%keys)) deallocate(heap%keys,stat=info)
!!$    if ((info == psb_success_).and.(allocated(heap%idxs))) deallocate(heap%idxs,stat=info)
!!$
!!$  end subroutine psb_free_int_idx_heap
!!$
!!$  subroutine psb_free_scomplex_idx_heap(heap,info)
!!$    implicit none 
!!$    type(psb_scomplex_idx_heap), intent(inout) :: heap
!!$    integer(psb_ipk_), intent(out)           :: info
!!$
!!$    info=psb_success_
!!$    if (allocated(heap%keys)) deallocate(heap%keys,stat=info)
!!$    if ((info == psb_success_).and.(allocated(heap%idxs))) deallocate(heap%idxs,stat=info)
!!$
!!$  end subroutine psb_free_scomplex_idx_heap
!!$
!!$  subroutine psb_free_dcomplex_idx_heap(heap,info)
!!$    implicit none 
!!$    type(psb_dcomplex_idx_heap), intent(inout) :: heap
!!$    integer(psb_ipk_), intent(out)           :: info
!!$
!!$    info=psb_success_
!!$    if (allocated(heap%keys)) deallocate(heap%keys,stat=info)
!!$    if ((info == psb_success_).and.(allocated(heap%idxs))) deallocate(heap%idxs,stat=info)
!!$
!!$  end subroutine psb_free_dcomplex_idx_heap
!!$

end module psb_sort_mod