-
Notifications
You must be signed in to change notification settings - Fork 83
/
DesignHashMap706.java
260 lines (232 loc) · 8.15 KB
/
DesignHashMap706.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
/**
* Design a HashMap without using any built-in hash table libraries.
*
* To be specific, your design should include these functions:
*
* put(key, value) : Insert a (key, value) pair into the HashMap. If the value
* already exists in the HashMap, update the value.
*
* get(key): Returns the value to which the specified key is mapped, or -1 if
* this map contains no mapping for the key.
*
* remove(key) : Remove the mapping for the value key if this map contains the
* mapping for the key.
*
* Example:
* MyHashMap hashMap = new MyHashMap();
* hashMap.put(1, 1);
* hashMap.put(2, 2);
* hashMap.get(1); // returns 1
* hashMap.get(3); // returns -1 (not found)
* hashMap.put(2, 1); // update the existing value
* hashMap.get(2); // returns 1
* hashMap.remove(2); // remove the mapping for 2
* hashMap.get(2); // returns -1 (not found)
*
* Note:
* All keys and values will be in the range of [0, 1000000].
* The number of operations will be in the range of [1, 10000].
* Please do not use the built-in HashMap library.
*/
public class DesignHashMap706 {
class MyHashMap {
private Integer[] cache = new Integer[1000000];
/** Initialize your data structure here. */
public MyHashMap() {
}
/** value will always be non-negative. */
public void put(int key, int value) {
cache[key] = value;
}
/** Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key */
public int get(int key) {
if (cache[key] == null) return -1;
return cache[key];
}
/** Removes the mapping of the specified value key if this map contains a mapping for the key */
public void remove(int key) {
cache[key] = null;
}
}
class MyHashMap2 {
private static final int K = 100000;
private ListNode[] cache = new ListNode[100000];
/** Initialize your data structure here. */
public MyHashMap() {
}
/** value will always be non-negative. */
public void put(int key, int value) {
int k = key % K;
if (cache[k] == null) {
cache[k] = new ListNode(key, value);
} else {
ListNode head = cache[k];
while (true) {
if (head.key == key) {
head.value = value;
return;
}
if (head.next == null) {
ListNode newNode = new ListNode(key, value);
head.next = newNode;
newNode.prev = head;
return;
}
head = head.next;
}
}
}
/** Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key */
public int get(int key) {
int k = key % K;
if (cache[k] == null) return -1;
ListNode head = cache[k];
while (true) {
if (head.key == key) {
return head.value;
}
if (head.next == null) {
return -1;
}
head = head.next;
}
}
/** Removes the mapping of the specified value key if this map contains a mapping for the key */
public void remove(int key) {
int k = key % K;
if (cache[k] == null) return;
ListNode head = cache[k];
while (true) {
if (head.key == key) {
if (head.prev == null) {
cache[k] = head.next;
} else {
if (head.next != null) head.next.prev = head.prev;
head.prev.next = head.next;
}
return;
}
if (head.next == null) {
return;
}
head = head.next;
}
}
class ListNode {
ListNode prev;
ListNode next;
Integer key;
Integer value;
ListNode (int key, int value) {
this.key = key;
this.value = value;
}
}
}
class MyHashMap3 {
private static final int K = 100000;
private TreeNode[] cache = new TreeNode[100000];
/** Initialize your data structure here. */
public MyHashMap() {
}
/** value will always be non-negative. */
public void put(int key, int value) {
int k = key % K;
if (cache[k] == null) {
cache[k] = new TreeNode(key, value);
} else {
TreeNode head = cache[k];
while (true) {
if (head.key == key) {
head.value = value;
return;
}
if (head.key > key) {
if (head.left == null) {
head.left = new TreeNode(key, value);
return;
}
head = head.left;
} else {
if (head.right == null) {
head.right = new TreeNode(key, value);
return;
}
head = head.right;
}
if (head == null) return;
}
}
}
/** Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key */
public int get(int key) {
int k = key % K;
if (cache[k] == null) return -1;
TreeNode head = cache[k];
while (true) {
if (head.key == key) {
return head.value;
}
if (head.key > key) {
if (head.left == null) {
return -1;
}
head = head.left;
} else {
if (head.right == null) {
return -1;
}
head = head.right;
}
if (head == null) return -1;
}
}
/** Removes the mapping of the specified value key if this map contains a mapping for the key */
public void remove(int key) {
int k = key % K;
cache[k] = delete(cache[k], key);
}
private TreeNode delete(TreeNode head, int key) {
if (head == null) return head;
if (key < head.key) {
head.left = delete(head.left, key);
} else if (key > head.key) {
head.right = delete(head.right, key);
} else {
if (head.left == null) {
return head.right;
} else if (head.right == null) {
return head.left;
}
head.key = minValue(head.right);
head.right = delete(head.right, head.key);
}
return head;
}
private int minValue(TreeNode head) {
int minv = head.key;
while (head.left != null) {
minv = head.left.key;
head = head.left;
}
return minv;
}
class TreeNode {
TreeNode left;
TreeNode right;
Integer key;
Integer value;
TreeNode (int key, int value) {
this.key = key;
this.value = value;
}
}
}
/**
* Your MyHashMap object will be instantiated and called as such:
* MyHashMap obj = new MyHashMap();
* obj.put(key,value);
* int param_2 = obj.get(key);
* obj.remove(key);
*/
}