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
|
#include <iostream>
#include <stack>
#include <queue>
#include <cstdlib>
using namespace std;
struct BSTNode {
int value;
BSTNode* left;
BSTNode* right;
};
void rInOrder(BSTNode* root);
void rPostOrder(BSTNode* root);
void unbalancedInsert(BSTNode* &head, int v)
{
//empty tree or foundlocation
if(head == NULL)
{
head = new BSTNode;
head->value = v;
head->left = NULL;
head->right = NULL;
}
else if(v < head->value)
{
unbalancedInsert(head->left, v);
}
else if(v > head->value)
{
unbalancedInsert(head->right, v);
}
else
{
cout << "Duplicate ignored" << endl;
}
}
void inOrder(BSTNode* root)
{
rInOrder(root); //calls recursive function
}
void postOrder(BSTNode* root)
{
rPostOrder(root); //calls recursive function
}
void preOrder(BSTNode* root)
{
stack<BSTNode*> Stacey;
BSTNode* top;
BSTNode* pop;
Stacey.push(root);
pop = Stacey.top();
while (!Stacey.empty() ) //while the stack is not empty traverse the tree using preorder traversal
{
top = Stacey.top();
cout << top->value << " ";
if (top->right->value == pop->value) //if the right node was just popped pop again (will eventually take to root)
{
pop = Stacey.top();
Stacey.pop();
}
else if (top->left != NULL && top->left->value != pop->value) //else if the left is not null and was not the last popped node
{ Stacey.push(top->left);}
else if (top->right != NULL) //else if the right node is not null
{ Stacey.push(top->right);}
else //else pop the stack
{
pop = top;
Stacey.pop();
}
}
}
void levelOrder(BSTNode* root)
{
BSTNode* next;
queue<BSTNode*> Quinn;
Quinn.push(root);
while (!Quinn.empty() ) //while the queue is not empty traverse the tree using level order traversal
{
next = Quinn.front();
Quinn.pop();
cout << next->value << " ";
if (next->left) //add left to the queue if not null
Quinn.push(next->left);
if (next->right) //and add right to the queue if not null
Quinn.push(next->right);
}
}
void rInOrder(BSTNode* root)
{
if (root == NULL) //if the passed in pointer is null go up a level
return;
else //else call the left recursive, display, and then call the right recursive
{
rInOrder(root->left);
cout << root->value << " ";
rInOrder(root->right);
}
}
void rPostOrder(BSTNode* root)
{
if (root == NULL) //if the passed in pointer is null go up a level
return;
else //else call the left recursive, call the right recursive, and then display the current
{
rPostOrder(root->left);
rPostOrder(root->right);
cout << root->value << " ";
}
}
int main() {
//create the tree
BSTNode* head = NULL;
unbalancedInsert(head, 54);
unbalancedInsert(head, 22);
unbalancedInsert(head, 17);
unbalancedInsert(head, 41);
unbalancedInsert(head, 36);
unbalancedInsert(head, 30);
unbalancedInsert(head, 74);
unbalancedInsert(head, 76);
unbalancedInsert(head, 26);
unbalancedInsert(head, 27);
unbalancedInsert(head, 45);
unbalancedInsert(head, 82);
cout << endl;
cout << "Ricky to the rescue:" << endl;
cout << "printing inorder: ";
inOrder(head);
cout << endl;
cout<< "Answer: 17 22 26 27 30 36 41 45 54 74 76 82";
cout << endl;
cout << endl;
cout << "printing postorder: ";
postOrder(head);
cout << endl;
cout <<"Answer: 17 27 26 30 36 45 41 22 82 76 74 54 ";
cout << endl;
cout << endl;
cout << endl;
cout << "Stacey saves the day" << endl;
cout << "printing preorder: ";
preOrder(head);
cout << endl;
cout <<"Answer: 54 22 17 41 36 30 26 27 45 74 76 82";
cout << endl;
cout << endl;
cout << "Quiet down, Quinn's in Town" << endl;
cout << "printing levelorder: ";
levelOrder(head);
cout << endl;
cout <<"Answer: 54 22 74 17 41 76 36 45 82 30 26 27";
cout << endl;
return 0;
}
|
