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feat: Update the implementation of hash_map_open_addressing.js and .ts (#881)

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* add permutations_ii.c and re-implement permutations_i.c

* Update the implementation of hash_map_open_addressing.js and .ts

* Update hash_map_open_addressing.js

* Update hash_map_open_addressing.js
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Yudong Jin 2023-10-24 23:46:34 +08:00 committed by GitHub
parent dbc76ec806
commit 19023148ba
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2 changed files with 203 additions and 172 deletions
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165
codes/javascript/chapter_hashing/hash_map_open_addressing.js
View File

@ -1,7 +1,7 @@
/**
* File: hash_map_open_addressing.js
* Created Time: 2023-08-06
* Author: yuan0221 (yl1452491917@gmail.com)
* File: hashMapOpenAddressing.js
* Created Time: 2023-06-13
* Author: yuan0221 (yl1452491917@gmail.com), Krahets (krahets@163.com)
*/
/* 键值对 Number -> String */
@ -19,16 +19,16 @@ class HashMapOpenAddressing {
#loadThres; // 触发扩容的负载因子阈值
#extendRatio; // 扩容倍数
#buckets; // 桶数组
#removed; // 删除标记
#TOMBSTONE; // 删除标记
/* 构造方法 */
constructor() {
this.#size = 0;
this.#capacity = 4;
this.#loadThres = 2.0 / 3.0;
this.#extendRatio = 2;
this.#buckets = new Array(this.#capacity).fill(null);
this.#removed = new Pair(-1, '-1');
this.#size = 0; // 键值对数量
this.#capacity = 4; // 哈希表容量
this.#loadThres = 2.0 / 3.0; // 触发扩容的负载因子阈值
this.#extendRatio = 2; // 扩容倍数
this.#buckets = Array(this.#capacity).fill(null); // 桶数组
this.#TOMBSTONE = new Pair(-1, '-1'); // 删除标记
}
/* 哈希函数 */
@ -41,22 +41,48 @@ class HashMapOpenAddressing {
return this.#size / this.#capacity;
}
/* 搜索 key 对应的桶索引 */
#findBucket(key) {
let index = this.#hashFunc(key);
let firstTombstone = -1;
// 线性探测，当遇到空桶时跳出
while (this.#buckets[index] !== null) {
// 若遇到 key ，返回对应桶索引
if (this.#buckets[index].key === key) {
// 若之前遇到了删除标记，则将键值对移动至该索引
if (firstTombstone !== -1) {
this.#buckets[firstTombstone] = this.#buckets[index];
this.#buckets[index] = this.#TOMBSTONE;
return firstTombstone; // 返回移动后的桶索引
}
return index; // 返回桶索引
}
// 记录遇到的首个删除标记
if (
firstTombstone === -1 &&
this.#buckets[index] === this.#TOMBSTONE
) {
firstTombstone = index;
}
// 计算桶索引，越过尾部返回头部
index = (index + 1) % this.#capacity;
}
// 若 key 不存在，则返回添加点的索引
return firstTombstone === -1 ? index : firstTombstone;
}
/* 查询操作 */
get(key) {
const index = this.#hashFunc(key);
// 线性探测，从 index 开始向后遍历
for (let i = 0; i < this.#capacity; i++) {
// 计算桶索引，越过尾部返回头部
const j = (index + i) % this.#capacity;
// 若遇到空桶，说明无此 key ，则返回 null
if (this.#buckets[j] === null) return null;
// 若遇到指定 key ，则返回对应 val
// 搜索 key 对应的桶索引
const index = this.#findBucket(key);
// 若找到键值对，则返回对应 val
if (
this.#buckets[j].key === key &&
this.#buckets[j].key !== this.#removed.key
)
return this.#buckets[j].val;
this.#buckets[index] !== null &&
this.#buckets[index] !== this.#TOMBSTONE
) {
return this.#buckets[index].val;
}
// 若键值对不存在，则返回 null
return null;
}
@ -66,45 +92,32 @@ class HashMapOpenAddressing {
if (this.#loadFactor() > this.#loadThres) {
this.#extend();
}
const index = this.#hashFunc(key);
// 线性探测，从 index 开始向后遍历
for (let i = 0; i < this.#capacity; i++) {
// 计算桶索引，越过尾部返回头部
let j = (index + i) % this.#capacity;
// 若遇到空桶、或带有删除标记的桶，则将键值对放入该桶
// 搜索 key 对应的桶索引
const index = this.#findBucket(key);
// 若找到键值对，则覆盖 val 并返回
if (
this.#buckets[j] === null ||
this.#buckets[j].key === this.#removed.key
this.#buckets[index] !== null &&
this.#buckets[index] !== this.#TOMBSTONE
) {
this.#buckets[j] = new Pair(key, val);
this.#size += 1;
this.#buckets[index].val = val;
return;
}
// 若遇到指定 key ，则更新对应 val
if (this.#buckets[j].key === key) {
this.#buckets[j].val = val;
return;
}
}
// 若键值对不存在，则添加该键值对
this.#buckets[index] = new Pair(key, val);
this.#size++;
}
/* 删除操作 */
remove(key) {
const index = this.#hashFunc(key);
// 线性探测，从 index 开始向后遍历
for (let i = 0; i < this.#capacity; i++) {
// 计算桶索引，越过尾部返回头部
const j = (index + i) % this.#capacity;
// 若遇到空桶，说明无此 key ，则直接返回
if (this.#buckets[j] === null) {
return;
}
// 若遇到指定 key ，则标记删除并返回
if (this.#buckets[j].key === key) {
this.#buckets[j] = this.#removed;
this.#size -= 1;
return;
}
// 搜索 key 对应的桶索引
const index = this.#findBucket(key);
// 若找到键值对，则用删除标记覆盖它
if (
this.#buckets[index] !== null &&
this.#buckets[index] !== this.#TOMBSTONE
) {
this.#buckets[index] = this.#TOMBSTONE;
this.#size--;
}
}
@ -114,11 +127,11 @@ class HashMapOpenAddressing {
const bucketsTmp = this.#buckets;
// 初始化扩容后的新哈希表
this.#capacity *= this.#extendRatio;
this.#buckets = new Array(this.#capacity).fill(null);
this.#buckets = Array(this.#capacity).fill(null);
this.#size = 0;
// 将键值对从原哈希表搬运至新哈希表
for (const pair of bucketsTmp) {
if (pair !== null && pair.key !== this.#removed.key) {
if (pair !== null && pair !== this.#TOMBSTONE) {
this.put(pair.key, pair.val);
}
}
@ -127,36 +140,38 @@ class HashMapOpenAddressing {
/* 打印哈希表 */
print() {
for (const pair of this.#buckets) {
if (pair !== null) {
console.log(pair.key + ' -> ' + pair.val);
} else {
if (pair === null) {
console.log('null');
} else if (pair === this.#TOMBSTONE) {
console.log('TOMBSTONE');
} else {
console.log(pair.key + ' -> ' + pair.val);
}
}
}
}
/* Driver Code */
/* 初始化哈希表 */
let map = new HashMapOpenAddressing();
// 初始化哈希表
const hashmap = new HashMapOpenAddressing();
/* 添加操作 */
// 在哈希表中添加键值对 (key, value)
map.put(12836, '小哈');
map.put(15937, '小啰');
map.put(16750, '小算');
map.put(13276, '小法');
map.put(10583, '小鸭');
// 添加操作
// 在哈希表中添加键值对 (key, val)
hashmap.put(12836, '小哈');
hashmap.put(15937, '小啰');
hashmap.put(16750, '小算');
hashmap.put(13276, '小法');
hashmap.put(10583, '小鸭');
console.log('\n添加完成后，哈希表为\nKey -> Value');
map.print();
hashmap.print();
/* 查询操作 */
// 向哈希表输入键 key ，得到值 value
const name = map.get(13276);
// 查询操作
// 向哈希表输入键 key ，得到值 val
const name = hashmap.get(13276);
console.log('\n输入学号 13276 ，查询到姓名 ' + name);
/* 删除操作 */
// 在哈希表中删除键值对 (key, value)
map.remove(16750);
// 删除操作
// 在哈希表中删除键值对 (key, val)
hashmap.remove(16750);
console.log('\n删除 16750 后，哈希表为\nKey -> Value');
map.print();
hashmap.print();

194
codes/typescript/chapter_hashing/hash_map_open_addressing.ts
View File

@ -1,13 +1,14 @@
/**
* File: hash_map_open_addressing.ts
* Created Time: 2023-08-06
* Author: yuan0221 (yl1452491917@gmail.com)
* Author: yuan0221 (yl1452491917@gmail.com), Krahets (krahets@163.com)
*/
/* 键值对 Number -> String */
class Pair {
key: number;
val: string;
constructor(key: number, val: string) {
this.key = key;
this.val = val;
@ -16,111 +17,124 @@ class Pair {
/* 开放寻址哈希表 */
class HashMapOpenAddressing {
#size: number; // 键值对数量
#capacity: number; // 哈希表容量
#loadThres: number; // 触发扩容的负载因子阈值
#extendRatio: number; // 扩容倍数
#buckets: Pair[]; // 桶数组
#removed: Pair; // 删除标记
private size: number; // 键值对数量
private capacity: number; // 哈希表容量
private loadThres: number; // 触发扩容的负载因子阈值
private extendRatio: number; // 扩容倍数
private buckets: Array<Pair | null>; // 桶数组
private TOMBSTONE: Pair; // 删除标记
/* 构造方法 */
constructor() {
this.#size = 0;
this.#capacity = 4;
this.#loadThres = 2.0 / 3.0;
this.#extendRatio = 2;
this.#buckets = new Array(this.#capacity).fill(null);
this.#removed = new Pair(-1, '-1');
this.size = 0; // 键值对数量
this.capacity = 4; // 哈希表容量
this.loadThres = 2.0 / 3.0; // 触发扩容的负载因子阈值
this.extendRatio = 2; // 扩容倍数
this.buckets = Array(this.capacity).fill(null); // 桶数组
this.TOMBSTONE = new Pair(-1, '-1'); // 删除标记
}
/* 哈希函数 */
#hashFunc(key: number): number {
return key % this.#capacity;
private hashFunc(key: number): number {
return key % this.capacity;
}
/* 负载因子 */
#loadFactor(): number {
return this.#size / this.#capacity;
private loadFactor(): number {
return this.size / this.capacity;
}
/* 搜索 key 对应的桶索引 */
private findBucket(key: number): number {
let index = this.hashFunc(key);
let firstTombstone = -1;
// 线性探测，当遇到空桶时跳出
while (this.buckets[index] !== null) {
// 若遇到 key ，返回对应桶索引
if (this.buckets[index]!.key === key) {
// 若之前遇到了删除标记，则将键值对移动至该索引
if (firstTombstone !== -1) {
this.buckets[firstTombstone] = this.buckets[index];
this.buckets[index] = this.TOMBSTONE;
return firstTombstone; // 返回移动后的桶索引
}
return index; // 返回桶索引
}
// 记录遇到的首个删除标记
if (
firstTombstone === -1 &&
this.buckets[index] === this.TOMBSTONE
) {
firstTombstone = index;
}
// 计算桶索引，越过尾部返回头部
index = (index + 1) % this.capacity;
}
// 若 key 不存在，则返回添加点的索引
return firstTombstone === -1 ? index : firstTombstone;
}
/* 查询操作 */
get(key: number): string | null {
const index = this.#hashFunc(key);
// 线性探测，从 index 开始向后遍历
for (let i = 0; i < this.#capacity; i++) {
// 计算桶索引，越过尾部返回头部
const j = (index + i) % this.#capacity;
// 若遇到空桶，说明无此 key ，则返回 null
if (this.#buckets[j] === null) return null;
// 若遇到指定 key ，则返回对应 val
// 搜索 key 对应的桶索引
const index = this.findBucket(key);
// 若找到键值对，则返回对应 val
if (
this.#buckets[j].key === key &&
this.#buckets[j].key !== this.#removed.key
)
return this.#buckets[j].val;
this.buckets[index] !== null &&
this.buckets[index] !== this.TOMBSTONE
) {
return this.buckets[index]!.val;
}
// 若键值对不存在，则返回 null
return null;
}
/* 添加操作 */
put(key: number, val: string): void {
// 当负载因子超过阈值时，执行扩容
if (this.#loadFactor() > this.#loadThres) {
this.#extend();
if (this.loadFactor() > this.loadThres) {
this.extend();
}
const index = this.#hashFunc(key);
// 线性探测，从 index 开始向后遍历
for (let i = 0; i < this.#capacity; i++) {
// 计算桶索引，越过尾部返回头部
let j = (index + i) % this.#capacity;
// 若遇到空桶、或带有删除标记的桶，则将键值对放入该桶
// 搜索 key 对应的桶索引
const index = this.findBucket(key);
// 若找到键值对，则覆盖 val 并返回
if (
this.#buckets[j] === null ||
this.#buckets[j].key === this.#removed.key
this.buckets[index] !== null &&
this.buckets[index] !== this.TOMBSTONE
) {
this.#buckets[j] = new Pair(key, val);
this.#size += 1;
this.buckets[index]!.val = val;
return;
}
// 若遇到指定 key ，则更新对应 val
if (this.#buckets[j].key === key) {
this.#buckets[j].val = val;
return;
}
}
// 若键值对不存在，则添加该键值对
this.buckets[index] = new Pair(key, val);
this.size++;
}
/* 删除操作 */
remove(key: number): void {
const index = this.#hashFunc(key);
// 线性探测，从 index 开始向后遍历
for (let i = 0; i < this.#capacity; i++) {
// 计算桶索引，越过尾部返回头部
const j = (index + i) % this.#capacity;
// 若遇到空桶，说明无此 key ，则直接返回
if (this.#buckets[j] === null) {
return;
}
// 若遇到指定 key ，则标记删除并返回
if (this.#buckets[j].key === key) {
this.#buckets[j] = this.#removed;
this.#size -= 1;
return;
}
// 搜索 key 对应的桶索引
const index = this.findBucket(key);
// 若找到键值对，则用删除标记覆盖它
if (
this.buckets[index] !== null &&
this.buckets[index] !== this.TOMBSTONE
) {
this.buckets[index] = this.TOMBSTONE;
this.size--;
}
}
/* 扩容哈希表 */
#extend(): void {
private extend(): void {
// 暂存原哈希表
const bucketsTmp = this.#buckets;
const bucketsTmp = this.buckets;
// 初始化扩容后的新哈希表
this.#capacity *= this.#extendRatio;
this.#buckets = new Array(this.#capacity).fill(null);
this.#size = 0;
this.capacity *= this.extendRatio;
this.buckets = Array(this.capacity).fill(null);
this.size = 0;
// 将键值对从原哈希表搬运至新哈希表
for (const pair of bucketsTmp) {
if (pair !== null && pair.key !== this.#removed.key) {
if (pair !== null && pair !== this.TOMBSTONE) {
this.put(pair.key, pair.val);
}
}
@ -128,39 +142,41 @@ class HashMapOpenAddressing {
/* 打印哈希表 */
print(): void {
for (const pair of this.#buckets) {
if (pair !== null) {
console.log(pair.key + ' -> ' + pair.val);
} else {
for (const pair of this.buckets) {
if (pair === null) {
console.log('null');
} else if (pair === this.TOMBSTONE) {
console.log('TOMBSTONE');
} else {
console.log(pair.key + ' -> ' + pair.val);
}
}
}
}
/* Driver Code */
/* 初始化哈希表 */
let map = new HashMapOpenAddressing();
// 初始化哈希表
const hashmap = new HashMapOpenAddressing();
/* 添加操作 */
// 在哈希表中添加键值对 (key, value)
map.put(12836, '小哈');
map.put(15937, '小啰');
map.put(16750, '小算');
map.put(13276, '小法');
map.put(10583, '小鸭');
// 添加操作
// 在哈希表中添加键值对 (key, val)
hashmap.put(12836, '小哈');
hashmap.put(15937, '小啰');
hashmap.put(16750, '小算');
hashmap.put(13276, '小法');
hashmap.put(10583, '小鸭');
console.log('\n添加完成后，哈希表为\nKey -> Value');
map.print();
hashmap.print();
/* 查询操作 */
// 向哈希表输入键 key ，得到值 value
const name = map.get(13276);
// 查询操作
// 向哈希表输入键 key ，得到值 val
const name = hashmap.get(13276);
console.log('\n输入学号 13276 ，查询到姓名 ' + name);
/* 删除操作 */
// 在哈希表中删除键值对 (key, value)
map.remove(16750);
// 删除操作
// 在哈希表中删除键值对 (key, val)
hashmap.remove(16750);
console.log('\n删除 16750 后，哈希表为\nKey -> Value');
map.print();
hashmap.print();
export {};