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Diffstat (limited to 'gcc-4.6/gcc/ada/g-hesora.ads')
-rw-r--r-- | gcc-4.6/gcc/ada/g-hesora.ads | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/gcc-4.6/gcc/ada/g-hesora.ads b/gcc-4.6/gcc/ada/g-hesora.ads new file mode 100644 index 000000000..11b896919 --- /dev/null +++ b/gcc-4.6/gcc/ada/g-hesora.ads @@ -0,0 +1,71 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- G N A T . H E A P _ S O R T _ A -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1995-2008, AdaCore -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 2, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- +-- for more details. You should have received a copy of the GNU General -- +-- Public License distributed with GNAT; see file COPYING. If not, write -- +-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- +-- Boston, MA 02110-1301, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- Heapsort using access to procedure parameters + +-- This package provides a heap sort routine that works with access to +-- subprogram parameters, so that it can be used with different types with +-- shared sorting code. It is considered obsoleted by GNAT.Heap_Sort which +-- offers a similar routine with a more convenient interface. + +-- This heapsort algorithm uses approximately N*log(N) compares in the +-- worst case and is in place with no additional storage required. See +-- the body for exact details of the algorithm used. + +pragma Compiler_Unit; + +package GNAT.Heap_Sort_A is + pragma Preelaborate; + + -- The data to be sorted is assumed to be indexed by integer values from + -- 1 to N, where N is the number of items to be sorted. In addition, the + -- index value zero is used for a temporary location used during the sort. + + type Move_Procedure is access procedure (From : Natural; To : Natural); + -- A pointer to a procedure that moves the data item with index From to + -- the data item with index To. An index value of zero is used for moves + -- from and to the single temporary location used by the sort. + + type Lt_Function is access function (Op1, Op2 : Natural) return Boolean; + -- A pointer to a function that compares two items and returns True if + -- the item with index Op1 is less than the item with index Op2, and False + -- if the Op1 item is greater than or equal to the Op2 item. + + procedure Sort (N : Natural; Move : Move_Procedure; Lt : Lt_Function); + -- This procedures sorts items in the range from 1 to N into ascending + -- order making calls to Lt to do required comparisons, and Move to move + -- items around. Note that, as described above, both Move and Lt use a + -- single temporary location with index value zero. This sort is not + -- stable, i.e. the order of equal elements in the input is not preserved. + +end GNAT.Heap_Sort_A; |