feat: 0981.Time-Based-Key-Value-Store

Author: kimi0230

Leetcode/0981.Time-Based-Key-Value-Store/README.md

@@ -0,0 +1,133 @@
+---
+title: 0981.Time Based Key-Value Store
+subtitle: "https://leetcode.com/problems/time-based-key-value-store/description/"
+date: 2024-01-22T21:20:00+08:00
+lastmod: 2024-01-22T21:20:00+08:00
+draft: false
+author: "Kimi.Tsai"
+authorLink: "https://kimi0230.github.io/"
+description: "0981.Time-Based-Key-Value-Store"
+license: ""
+images: []
+
+tags: [LeetCode, Go, Medium, Time Based Key-Value Store, Hash Table, String, Binary Search, Design]
+categories: [LeetCode]
+
+featuredImage: ""
+featuredImagePreview: ""
+
+hiddenFromHomePage: false
+hiddenFromSearch: false
+twemoji: false
+lightgallery: true
+ruby: true
+fraction: true
+fontawesome: true
+linkToMarkdown: false
+rssFullText: false
+
+toc:
+  enable: true
+  auto: true
+code:
+  copy: true
+  maxShownLines: 200
+math:
+  enable: false
+  # ...
+mapbox:
+  # ...
+share:
+  enable: true
+  # ...
+comment:
+  enable: true
+  # ...
+library:
+  css:
+    # someCSS = "some.css"
+    # located in "assets/"
+    # Or
+    # someCSS = "https://cdn.example.com/some.css"
+  js:
+    # someJS = "some.js"
+    # located in "assets/"
+    # Or
+    # someJS = "https://cdn.example.com/some.js"
+seo:
+  images: []
+  # ...
+---
+# [0981.Time Based Key-Value Store](https://leetcode.com/problems/time-based-key-value-store/description/)
+
+## 題目
+
+## 題目大意
+
+
+## 解題思路
+
+## Big O
+
+* 時間複雜 : ``
+* 空間複雜 : ``
+
+## 來源
+* https://leetcode.com/problems/time-based-key-value-store/description/
+* https://leetcode.cn/problems/
+
+## 解答
+https://github.com/kimi0230/LeetcodeGolang/blob/master/Leetcode/0981.Time-Based-Key-Value-Store/main.go
+
+```go
+package timebasedkeyvaluestore
+
+import "sort"
+
+// 時間複雜 O(), 空間複雜 O()
+type element struct {
+	key       string
+	value     string
+	timestamp int
+}
+
+type TimeMap struct {
+	elements map[string][]element
+}
+
+func Constructor() TimeMap {
+	return TimeMap{elements: make(map[string][]element)}
+}
+
+func (this *TimeMap) Set(key string, value string, timestamp int) {
+	this.elements[key] = append(this.elements[key], element{
+		key:       key,
+		value:     value,
+		timestamp: timestamp,
+	})
+}
+
+// O(log n)
+func (this *TimeMap) Get(key string, timestamp int) string {
+	if _, ok := this.elements[key]; !ok {
+		return ""
+	}
+	// 二分法找出符合條件的最左邊
+	index := sort.Search(len(this.elements[key]), func(i int) bool {
+		return this.elements[key][i].timestamp > timestamp
+	})
+	if index == 0 {
+		return ""
+	}
+
+	index--
+	return this.elements[key][index].value
+}
+
+```
+
+##  Benchmark
+
+```sh
+
+```

Leetcode/0981.Time-Based-Key-Value-Store/main.go

@@ -0,0 +1,43 @@
+package timebasedkeyvaluestore
+
+import "sort"
+
+// 時間複雜 O(), 空間複雜 O()
+type element struct {
+	key       string
+	value     string
+	timestamp int
+}
+
+type TimeMap struct {
+	elements map[string][]element
+}
+
+func Constructor() TimeMap {
+	return TimeMap{elements: make(map[string][]element)}
+}
+
+func (this *TimeMap) Set(key string, value string, timestamp int) {
+	this.elements[key] = append(this.elements[key], element{
+		key:       key,
+		value:     value,
+		timestamp: timestamp,
+	})
+}
+
+// O(log n)
+func (this *TimeMap) Get(key string, timestamp int) string {
+	if _, ok := this.elements[key]; !ok {
+		return ""
+	}
+	// 二分法找出符合條件的最左邊
+	index := sort.Search(len(this.elements[key]), func(i int) bool {
+		return this.elements[key][i].timestamp > timestamp
+	})
+	if index == 0 {
+		return ""
+	}
+
+	index--
+	return this.elements[key][index].value
+}

Leetcode/0981.Time-Based-Key-Value-Store/main_test.go

@@ -0,0 +1,50 @@
+package timebasedkeyvaluestore
+
+import (
+	"testing"
+)
+
+func TestTimeMap(t *testing.T) {
+	timeMap := Constructor()
+	timeMap.Set("foo", "bar", 1)
+	timeMap.Set("foo", "bar2", 4)
+	timeMap.Set("foo", "bar3", 6)
+
+	tests := []struct {
+		key       string
+		timestamp int
+		want      string
+	}{
+		{"foo", 1, "bar"},
+		{"foo", 3, "bar"},
+		{"foo", 4, "bar2"},
+		{"foo", 5, "bar2"},
+		{"foo", 6, "bar3"},
+		{"foo", 7, "bar3"},
+		{"foo2", 1, ""},
+	}
+
+	for _, tt := range tests {
+		got := timeMap.Get(tt.key, tt.timestamp)
+		if got != tt.want {
+			t.Errorf("Get(%v, %v) = %v, want %v", tt.key, tt.timestamp, got, tt.want)
+		}
+	}
+}
+
+func BenchmarkTimeMap_Get(b *testing.B) {
+	timeMap := Constructor()
+	timeMap.Set("foo", "bar", 1)
+	timeMap.Set("foo", "bar2", 4)
+	timeMap.Set("foo", "bar3", 6)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		timeMap.Get("foo", 5)
+	}
+}
+
+/*
+go test -benchmem -run=none LeetcodeGolang/Leetcode/0354.Russian-Doll-Envelopes -bench=.
+
+*/

Leetcode_labuladong/981.基于时间的键值存储.go

@@ -0,0 +1,114 @@
+// 時間複雜度:
+// 空間複雜度:
+/*
+ * @lc app=leetcode.cn id=981 lang=golang
+ *
+ * [981] 基于时间的键值存储
+ *
+ * https://leetcode.cn/problems/time-based-key-value-store/description/
+ *
+ * algorithms
+ * Medium (52.55%)
+ * Likes:    226
+ * Dislikes: 0
+ * Total Accepted:    32.9K
+ * Total Submissions: 62.7K
+ * Testcase Example:  '["TimeMap","set","get","get","set","get","get"]\n' +
+  '[[],["foo","bar",1],["foo",1],["foo",3],["foo","bar2",4],["foo",4],["foo",5]]'
+ *
+ * 设计一个基于时间的键值数据结构，该结构可以在不同时间戳存储对应同一个键的多个值，并针对特定时间戳检索键对应的值。
+ *
+ * 实现 TimeMap 类：
+ *
+ *
+ * TimeMap() 初始化数据结构对象
+ * void set(String key, String value, int timestamp) 存储给定时间戳 timestamp 时的键 key
+ * 和值 value。
+ * String get(String key, int timestamp) 返回一个值，该值在之前调用了 set，其中 timestamp_prev
+ * <= timestamp 。如果有多个这样的值，它将返回与最大  timestamp_prev 关联的值。如果没有值，则返回空字符串（""）。
+ *
+ *
+ *
+ * 示例 1：
+ *
+ *
+ * 输入：
+ * ["TimeMap", "set", "get", "get", "set", "get", "get"]
+ * [[], ["foo", "bar", 1], ["foo", 1], ["foo", 3], ["foo", "bar2", 4], ["foo",
+ * 4], ["foo", 5]]
+ * 输出：
+ * [null, null, "bar", "bar", null, "bar2", "bar2"]
+ *
+ * 解释：
+ * TimeMap timeMap = new TimeMap();
+ * timeMap.set("foo", "bar", 1);  // 存储键 "foo" 和值 "bar" ，时间戳 timestamp = 1
+ * timeMap.get("foo", 1);         // 返回 "bar"
+ * timeMap.get("foo", 3);         // 返回 "bar", 因为在时间戳 3 和时间戳 2 处没有对应 "foo"
+ * 的值，所以唯一的值位于时间戳 1 处（即 "bar"） 。
+ * timeMap.set("foo", "bar2", 4); // 存储键 "foo" 和值 "bar2" ，时间戳 timestamp = 4
+ * timeMap.get("foo", 4);         // 返回 "bar2"
+ * timeMap.get("foo", 5);         // 返回 "bar2"
+ *
+ *
+ *
+ *
+ * 提示：
+ *
+ *
+ * 1 <= key.length, value.length <= 100
+ * key 和 value 由小写英文字母和数字组成
+ * 1 <= timestamp <= 10^7
+ * set 操作中的时间戳 timestamp 都是严格递增的
+ * 最多调用 set 和 get 操作 2 * 10^5 次
+ *
+ *
+*/
+
+// @lc code=start
+
+type element struct {
+	key       string
+	value     string
+	timestamp int
+}
+
+type TimeMap struct {
+	elements map[string][]element
+}
+
+func Constructor() TimeMap {
+	return TimeMap{elements: make(map[string][]element)}
+}
+
+func (this *TimeMap) Set(key string, value string, timestamp int) {
+	this.elements[key] = append(this.elements[key], element{
+		key:       key,
+		value:     value,
+		timestamp: timestamp,
+	})
+}
+
+func (this *TimeMap) Get(key string, timestamp int) string {
+	if _, ok := this.elements[key]; !ok {
+		return ""
+	}
+	// 二分法找出符合條件的最左邊
+	index := sort.Search(len(this.elements[key]), func(i int) bool {
+		return this.elements[key][i].timestamp > timestamp
+	})
+	if index == 0 {
+		return ""
+	}
+
+	index--
+	return this.elements[key][index].value
+}
+
+/**
+ * Your TimeMap object will be instantiated and called as such:
+ * obj := Constructor();
+ * obj.Set(key,value,timestamp);
+ * param_2 := obj.Get(key,timestamp);
+ */
+// @lc code=end
+

README.md

@@ -524,6 +524,7 @@ func search(nums []int, target int) int {
 | [0153](https://kimi0230.github.io/LeetcodeGolang/Leetcode/0153.Find-Minimum-in-Rotated-Sorted-Array/)                    |                   [153. Find Minimum in Rotated Sorted Array](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/description/)                    |          [Go](https://github.com/kimi0230/LeetcodeGolang/tree/master/Leetcode/0153.Find-Minimum-in-Rotated-Sorted-Array)           | Medium     | O(log n）                             | O(1)                          | Binary Search |
 | [0033](https://kimi0230.github.io/LeetcodeGolang/Leetcode/0033.Search-in-Rotated-Sorted-Array/)                          |                         [33. Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/description//)                          |             [Go](https://github.com/kimi0230/LeetcodeGolang/tree/master/Leetcode/0033.Search-in-Rotated-Sorted-Array)              | Medium     | O(log n）                             | O(1)                          | Binary Search |
 | [0034](https://kimi0230.github.io/LeetcodeGolang/Leetcode/0034.Find-First-and-Last-Position-of-Element-in-Sorted-Array/) | [34. Find First and Last Position of Element in Sorted Array](https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/description/) | [Go](https://github.com/kimi0230/LeetcodeGolang/tree/master/Leetcode/0034.Find-First-and-Last-Position-of-Element-in-Sorted-Array) | Medium     | O(log n）                             | O(1)                          | Binary Search |
+| [0981](https://kimi0230.github.io/LeetcodeGolang/Leetcode/0981.Time-Based-Key-Value-Store/)                              |                             [0981.Time Based Key-Value Store](https://leetcode.com/problems/time-based-key-value-store/description/)                              |               [Go](https://github.com/kimi0230/LeetcodeGolang/tree/master/Leetcode/0981.Time-Based-Key-Value-Store)                | Medium     | O(log n）                             |                               | Binary Search |
 
 
 ---