1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
------------------------------------------------------------------------------
-- --
-- GNAT LIBRARY COMPONENTS --
-- --
-- ADA.CONTAINERS.GENERIC_SORT --
-- --
-- B o d y --
-- --
-- Copyright (C) 2011, Free Software Foundation, Inc. --
-- --
-- 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 3, 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. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- This unit was originally developed by Matthew J Heaney. --
------------------------------------------------------------------------------
-- This algorithm was adapted from GNAT.Heap_Sort (see g-heasor.ad[sb])
with System;
procedure Ada.Containers.Generic_Sort (First, Last : Index_Type'Base) is
type T is range System.Min_Int .. System.Max_Int;
function To_Index (J : T) return Index_Type;
pragma Inline (To_Index);
function Lt (J, K : T) return Boolean;
pragma Inline (Lt);
procedure Xchg (J, K : T);
pragma Inline (Xchg);
procedure Sift (S : T);
--------------
-- To_Index --
--------------
function To_Index (J : T) return Index_Type is
K : constant T'Base := Index_Type'Pos (First) + J - T'(1);
begin
return Index_Type'Val (K);
end To_Index;
--------
-- Lt --
--------
function Lt (J, K : T) return Boolean is
begin
return Before (To_Index (J), To_Index (K));
end Lt;
----------
-- Xchg --
----------
procedure Xchg (J, K : T) is
begin
Swap (To_Index (J), To_Index (K));
end Xchg;
Max : T := Index_Type'Pos (Last) - Index_Type'Pos (First) + T'(1);
----------
-- Sift --
----------
procedure Sift (S : T) is
C : T := S;
Son : T;
Father : T;
begin
loop
Son := C + C;
if Son < Max then
if Lt (Son, Son + 1) then
Son := Son + 1;
end if;
elsif Son > Max then
exit;
end if;
Xchg (Son, C);
C := Son;
end loop;
while C /= S loop
Father := C / 2;
if Lt (Father, C) then
Xchg (Father, C);
C := Father;
else
exit;
end if;
end loop;
end Sift;
-- Start of processing for Generic_Sort
begin
for J in reverse 1 .. Max / 2 loop
Sift (J);
end loop;
while Max > 1 loop
Xchg (1, Max);
Max := Max - 1;
Sift (1);
end loop;
end Ada.Containers.Generic_Sort;
|
