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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
#!/usr/bin/env perl
use strict;
use warnings;
use Tree::DAG_Node;
my($starting_node);
# -----------------------------------------------
sub grow_tree
{
my($count) = 0;
my($tree) = Tree::DAG_Node -> new({name => 'Root', attributes => {'#' => $count} });
my(%child) =
(
I => 'J',
H => 'J',
J => 'L',
L => 'M',
D => 'F',
E => 'F',
F => 'G',
B => 'C',
);
my($child);
my($kid_1, $kid_2);
my($name, $node);
for $name (qw/I H J J L D E F B/)
{
$count++;
$node = Tree::DAG_Node -> new({name => $name, attributes => {'#' => $count} });
$child = Tree::DAG_Node -> new({name => $child{$name}, attributes => {'#' => $count} });
$starting_node = $node if ($name eq 'H');
$child -> name('K') if ($count == 3);
if ($child{$name} eq 'M')
{
$kid_1 = Tree::DAG_Node -> new({name => 'N', attributes => {'#' => $count}});
$kid_2 = Tree::DAG_Node -> new({name => 'O', attributes => {'#' => $count}});
$kid_1 -> add_daughter($kid_2);
$child -> add_daughter($kid_1);
}
$node -> add_daughter($child);
$tree -> add_daughter($node);
}
return $tree;
} # End of grow_tree.
# -----------------------------------------------
sub process_tree_helper
{
my($tree) = @_;
my(@ancestors) = map{$_ -> name} $tree -> daughters;
my(%ancestors);
@ancestors{@ancestors} = (1) x @ancestors;
my($attributes);
my($name);
my(@stack);
$tree -> walk_down
({
ancestors => \%ancestors,
callback =>
sub
{
my($node, $options) = @_;
if ($$options{_depth} > 1)
{
$attributes = $node -> attributes;
$name = $node -> name;
if (defined $$options{ancestors}{$name} && ! $$attributes{replaced})
{
push @{$$options{stack} }, $node;
}
}
return 1;
},
_depth => 0,
stack => \@stack,
});
my($sub_tree) = Tree::DAG_Node -> new;
my(@kids);
my($node);
my(%seen);
for $node (@stack)
{
$name = $node -> name;
@kids = grep{$_ -> name eq $name} $tree -> daughters;
$seen{$name} = 1;
$sub_tree -> add_daughters(map{$_ -> copy_at_and_under({no_attribute_copy => 1})} @kids);
for ($sub_tree -> daughters)
{
$_ -> attributes({%{$_ -> attributes}, replaced => 1});
}
$node -> replace_with($sub_tree -> daughters);
}
return ({%seen}, $#stack);
} # End of process_tree_helper.
# ------------------------------------------------
sub process_tree
{
my($tree) = @_;
my($finished) = 0;
my(@result);
my(%seen);
while (! $finished)
{
@result = process_tree_helper($tree);
$seen{$_} = 1 for keys %{$result[0]};
$finished = $result[1] < 0;
}
for my $child ($tree -> daughters)
{
$tree -> remove_daughter($child) if ($seen{$child -> name});
}
} # End of process_tree.
# -----------------------------------------------
my($tree) = grow_tree;
my(@ascii_1) = @{$tree -> draw_ascii_tree};
my(@string_1) = @{$tree -> tree2string};
my(@string_2) = @{$tree -> tree2string({no_attributes => 1})};
my(@string_3) = @{$tree -> tree2string({}, $starting_node)};
process_tree($tree);
print "1: draw_ascii_tree(): Before: \n";
print map{"$_\n"} @ascii_1;
print "2: draw_ascii_tree(): After: \n";
print map{"$_\n"} @{$tree -> draw_ascii_tree};
print '-' x 35, "\n";
print "3: tree2string(): Before: \n";
print map{"$_\n"} @string_1;
print "4: tree2string(): After: \n";
print map{"$_\n"} @{$tree -> tree2string};
print '-' x 35, "\n";
print "5: tree2string({no_attributes => 1}): Before: \n";
print map{"$_\n"} @string_2;
print "6: tree2string({no_attributes => 1}): After: \n";
print map{"$_\n"} @{$tree -> tree2string({no_attributes => 1})};
print '-' x 35, "\n";
print "5: tree2string({}, \$starting_node) before: \n";
print map{"$_\n"} @string_3;
print "6: tree2string({}, \$starting_node) after: \n";
print map{"$_\n"} @{$tree -> tree2string({}, $starting_node)};
print '-' x 35, "\n";
print "Warning: Don't try this at home kids. Some trees get into an infinite loop.\n";
|
