-
Notifications
You must be signed in to change notification settings - Fork 0
/
BTree.java
146 lines (127 loc) · 2.83 KB
/
BTree.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
import java.io.*;
import java.util.*;
class Node{
String word;
Node left;
Node right;
public Node(String word){
this.word = word;
left = null;
right = null;
}
}
class BTree{
public static Node root; //Root Node
public BTree(){
this.root=null;
}
public BTree(Node root){
this.root=root;
}
public static boolean isEmpty(){ //O(1)
return (root==null);
}
public static int size(){
return size(root);
}
private static int size(Node n){
if(n==null) return 0;
else return 1 + size(n.left) + size(n.right);
}
public static int depth (){
return depth(root);
}
private static int depth(Node n){
if(n==null) return 0;
else{
int count = 1 + Math.max(depth(n.left),depth(n.right));
return count;
}
}
public static void insert(String w){ //O(log n)
root = insert(root,w);
}
private static Node insert(Node n,String w){
if(n==null) return new Node(w);
else{
int cmp=w.compareTo(n.word);
if(cmp==0) return n; //its already on the list
else if(cmp < 0) n.left = insert(n.left,w);
else n.right=insert(n.right,w);
}
return n;
}
public static boolean contains(String w){ //O(log n)
return contains(root,w);
}
private static boolean contains(Node n,String w){
if(n==null) return false;
else{
int cmp=w.compareTo(n.word);
if(cmp==0) return true;
else if(cmp < 0) return contains(n.left,w);
else return contains(n.right,w);
}
}
public static void remove(String w){ //O(log n)
root = remove(root,w);
}
private static Node remove(Node n,String w){
if(n!=null){
int cmp=w.compareTo(n.word);
if(cmp < 0) n.left = remove(n.left,w);
else if(cmp > 0) n.right = remove(n.right,w);
else if(n.left==null) n=n.right;
else if(n.right==null) n=n.left;
else{
n.right = removeMin(n,n.right);
}
}
return n;
}
private static Node removeMin(Node n1,Node n2){
if(n2.left==null){
n1.word=n2.word;
return n2.right;
}
else
n2.left = removeMin(n1,n2.left);
return n2;
}
public static void view(){ //O(n) !!!SWITCH
view(root);
}
private static void view(Node n){
if(n.left!=null) view(n.left);
System.out.println(n.word );
if(n.right!=null) view(n.right);
return;
}
public static String first(){ //O(log n)
if(root==null) return ("Tree is empty!");
return first(root);
}
private static String first(Node n){
if(n.left==null) return n.word;
else return (first(n.left));
}
public static String last(){ //O(log n)
if(root==null) return ("Tree is empty!");
return last(root);
}
private static String last(Node n){
if(n.right==null) return n.word;
else return (last(n.right));
}
public static long count(int d){
return count(root,d,0);
}
private static long count(Node n,int d,int c){
if(n==null) return 0;
if(d==c) return 1;
else{
long l =count(n.left,d,c+1) + count(n.right,d,c+1);
return l;
}
}
}