destroy.c
2.3 KB
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
/**
* \file
*
* \author Georg Hopp
*
* \copyright
* Copyright © 2012 Georg Hopp
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT 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
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "tree.h"
void
treeDestroy(Tree * this, TreeAction action)
{
Tree previous = * this;
Tree node = * this;
int depth = 1;
/*
* I think this has something like O(n+log(n)) on a ballanced
* tree because I have to traverse back the rightmost leaf to
* the root to get a break condition.
*/
while (NULL != node) {
/*
* If we come from the right so nothing and go to our
* next parent.
*/
if (((NULL == TREE_LEFT(node)
|| previous == TREE_LEFT(node)) && NULL == TREE_RIGHT(node))
|| previous == TREE_RIGHT(node)) {
Tree parent = TREE_PARENT(node);
action(node->data, depth);
previous = node;
delete(node);
node = parent;
depth--;
continue;
}
if ((NULL == TREE_LEFT(node) || previous == TREE_LEFT(node))) {
/*
* If there are no more elements to the left or we
* came from the left, process data.
*/
previous = node;
if (NULL != TREE_RIGHT(node)) {
node = TREE_RIGHT(node);
depth++;
} else {
node = TREE_PARENT(node);
depth--;
}
} else {
/*
* if there are more elements to the left go there.
*/
previous = node;
node = TREE_LEFT(node);
depth++;
}
}
*this = NULL;
}
// vim: set ts=4 sw=4: