-
Notifications
You must be signed in to change notification settings - Fork 0
/
BinaryTree.java
279 lines (236 loc) · 6.66 KB
/
BinaryTree.java
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
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
// Basic tree traversal
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import java.util.Stack;
public class BinaryTree {
private BinaryTreeNode root;
public BinaryTree() {
}
// constructor
public BinaryTree(BinaryTreeNode root) {
this.root = root;
}
// setter and getter
public void setRoot(BinaryTreeNode root) {
this.root = root;
}
public BinaryTreeNode getRoot() {
return root;
}
// Pre-order traversal recursive
public void preOrderTraversal(BinaryTreeNode root) {
if(root != null) {
System.out.print(root.value + " ");
preOrderTraversal(root.left);
preOrderTraversal(root.right);
}
}
// Pre-order traversal iteratively
public void preOrderIterative(BinaryTreeNode root) {
if(root == null)
return;
BinaryTreeNode rootTemp = root;
Stack<BinaryTreeNode> stack = new Stack<>();
stack.push(rootTemp);
while(!stack.isEmpty()) {
BinaryTreeNode temp = stack.pop();
System.out.print(temp.value + " ");
if(temp.right != null)
stack.push(temp.right);
if(temp.left != null)
stack.push(temp.left);
}
}
// In order Traversal
public void inOrderTraversal(BinaryTreeNode root) {
if(root != null) {
inOrderTraversal(root.left);
System.out.print(root.value + " ");
inOrderTraversal(root.right);
}
}
// In Order Iterative
public void inOrder(BinaryTreeNode root) {
if(root == null)
return;
BinaryTreeNode temp = root;
Stack<BinaryTreeNode> stack = new Stack<>();
stack.push(temp);
while(true) {
if(temp.left != null) {
stack.push(temp.left);
temp = temp.left;
}
else {
if(stack.isEmpty())
break;
else {
System.out.print(stack.pop().value + " ");
temp = temp.right;
}
}
}
}
// Post Order Traversal
public void postOrderTraversal(BinaryTreeNode root) {
if(root != null) {
postOrderTraversal(root.left);
postOrderTraversal(root.right);
System.out.print(root.value + " ");
}
}
public void postOrderI(BinaryTreeNode root) {
if(root == null)
return;
BinaryTreeNode current = root;
Stack<BinaryTreeNode> stackOne = new Stack<>();
Stack<BinaryTreeNode> stackTwo = new Stack<>();
stackOne.push(root);
while(!stackOne.isEmpty()) {
current = stackOne.pop();
stackTwo.push(current);
if(current.left != null)
stackOne.push(current);
if(current.right != null)
stackTwo.push(current);
}
while(!stackTwo.isEmpty())
System.out.println(stackTwo.pop().value);
}
// Level Order Traversal
public void levelOrder(BinaryTreeNode root) {
if(root == null)
return;
BinaryTreeNode current = root;
Queue<BinaryTreeNode> queue = new LinkedList<>();
queue.add(current);
while(!queue.isEmpty()) {
current = queue.poll();
System.out.print(current.value + " ");
if(current.left != null)
queue.add(current.left);
if(current.right != null)
queue.add(current.right);
}
}
// Vertical Order Traversal
public void vertialOrder(BinaryTreeNode root) {
if(root == null)
return;
Queue<BinaryTreeNode> nodes = new LinkedList<>();
Queue<Integer> horizontalDist = new LinkedList<>();
Map<Integer, ArrayList<BinaryTreeNode>> map = new HashMap<>();
nodes.add(root);
horizontalDist.add(0);
while(!nodes.isEmpty()) {
BinaryTreeNode current = nodes.poll();
Integer hd = horizontalDist.poll();
if(map.containsKey(hd)){
ArrayList<BinaryTreeNode> temp = map.get(hd);
temp.add(current);
map.put(hd, temp);
}
else {
ArrayList<BinaryTreeNode> temp = new ArrayList<>();
temp.add(current);
map.put(hd, temp);
}
if(current.left != null) {
nodes.add(current.left);
horizontalDist.add(hd-1);
}
if(current.right != null) {
nodes.add(current.right);
horizontalDist.add(hd+1);
}
}
Set<Integer> set = map.keySet();
List<Integer> list = new LinkedList<>();
list.addAll(set);
Collections.sort(list, new Comparator<Integer>() {
@Override
public int compare(Integer o1, Integer o2) {
return o1.compareTo(o2);
}
});
for(Integer integer:list) {
ArrayList<BinaryTreeNode> temp = map.get(integer);
System.out.print(temp.get(0).value+" ");
}
}
public BinaryTreeNode treeExample() {
BinaryTreeNode temp = getRoot();
temp.value = 1;
temp.left = new BinaryTreeNode(2);
temp.right = new BinaryTreeNode(3);
temp.left.left = new BinaryTreeNode(4);
temp.left.right = new BinaryTreeNode(5);
temp.right.left = new BinaryTreeNode(6);
temp.right.right = new BinaryTreeNode(7);
return temp;
}
public BinaryTreeNode treeExample1() {
BinaryTreeNode temp = getRoot();
temp.value = 1;
temp.left = new BinaryTreeNode(2);
temp.right = new BinaryTreeNode(3);
temp.left.left = new BinaryTreeNode(4);
temp.left.right = new BinaryTreeNode(5);
temp.right.left = new BinaryTreeNode(6);
temp.right.right = new BinaryTreeNode(7);
temp.right.left.right = new BinaryTreeNode(8);
temp.right.right.right = new BinaryTreeNode(9);
return temp;
}
public BinaryTreeNode treeExample2() {
BinaryTreeNode temp = getRoot();
temp.value = 1;
temp.right = new BinaryTreeNode(2);
temp.right.right = new BinaryTreeNode(5);
temp.right.right.right = new BinaryTreeNode(6);
temp.right.right.left = new BinaryTreeNode(3);
temp.right.right.left.right = new BinaryTreeNode(4);
return temp;
}
public static void main(String[] args) {
BinaryTreeNode temp = new BinaryTreeNode(1);
BinaryTree binaryTree = new BinaryTree();
binaryTree.root = temp;
/*System.out.println("Pre Order Traversal");
binaryTree.preOrderTraversal(binaryTree.treeExample());
System.out.println();
System.out.println("Pre Order Traversal Iteratively");
binaryTree.preOrderIterative(binaryTree.treeExample());
System.out.println();
System.out.println("In Order Traversal");
binaryTree.inOrderTraversal(binaryTree.treeExample());
System.out.println();
System.out.println("In Order Traversal Iteratively");
binaryTree.inOrderTraversal(binaryTree.treeExample());
System.out.println();
System.out.println("Post Order Traversal");
binaryTree.postOrderTraversal(binaryTree.treeExample());
System.out.println();
System.out.println("Level Order Traversal");
binaryTree.levelOrder(binaryTree.treeExample());
System.out.println();*/
System.out.println("Vertical Order Traversal");
binaryTree.vertialOrder(binaryTree.treeExample2());
}
}
// Binary Tree Nodes class
class BinaryTreeNode {
public int value;
public BinaryTreeNode left;
public BinaryTreeNode right;
public BinaryTreeNode(int value) {
this.value = value;
}
}