{ "data": { "question": { "questionId": "1023", "questionFrontendId": "981", "boundTopicId": null, "title": "Time Based Key-Value Store", "titleSlug": "time-based-key-value-store", "content": "

Design a time-based key-value data structure that can store multiple values for the same key at different time stamps and retrieve the key's value at a certain timestamp.

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Implement the TimeMap class:

\n\n\n\n

 

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Example 1:

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\nInput\n["TimeMap", "set", "get", "get", "set", "get", "get"]\n[[], ["foo", "bar", 1], ["foo", 1], ["foo", 3], ["foo", "bar2", 4], ["foo", 4], ["foo", 5]]\nOutput\n[null, null, "bar", "bar", null, "bar2", "bar2"]\n\nExplanation\nTimeMap timeMap = new TimeMap();\ntimeMap.set("foo", "bar", 1);  // store the key "foo" and value "bar" along with timestamp = 1.\ntimeMap.get("foo", 1);         // return "bar"\ntimeMap.get("foo", 3);         // return "bar", since there is no value corresponding to foo at timestamp 3 and timestamp 2, then the only value is at timestamp 1 is "bar".\ntimeMap.set("foo", "bar2", 4); // store the key "foo" and value "bar2" along with timestamp = 4.\ntimeMap.get("foo", 4);         // return "bar2"\ntimeMap.get("foo", 5);         // return "bar2"\n
\n\n

 

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Constraints:

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"codeSnippets": [ { "lang": "C++", "langSlug": "cpp", "code": "class TimeMap {\npublic:\n TimeMap() {\n \n }\n \n void set(string key, string value, int timestamp) {\n \n }\n \n string get(string key, int timestamp) {\n \n }\n};\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * TimeMap* obj = new TimeMap();\n * obj->set(key,value,timestamp);\n * string param_2 = obj->get(key,timestamp);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Java", "langSlug": "java", "code": "class TimeMap {\n\n public TimeMap() {\n \n }\n \n public void set(String key, String value, int timestamp) {\n \n }\n \n public String get(String key, int timestamp) {\n \n }\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * TimeMap obj = new TimeMap();\n * obj.set(key,value,timestamp);\n * String param_2 = obj.get(key,timestamp);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Python", "langSlug": "python", "code": "class TimeMap(object):\n\n def __init__(self):\n \n\n def set(self, key, value, timestamp):\n \"\"\"\n :type key: str\n :type value: str\n :type timestamp: int\n :rtype: None\n \"\"\"\n \n\n def get(self, key, timestamp):\n \"\"\"\n :type key: str\n :type timestamp: int\n :rtype: str\n \"\"\"\n \n\n\n# Your TimeMap object will be instantiated and called as such:\n# obj = TimeMap()\n# obj.set(key,value,timestamp)\n# param_2 = obj.get(key,timestamp)", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "class TimeMap:\n\n def __init__(self):\n \n\n def set(self, key: str, value: str, timestamp: int) -> None:\n \n\n def get(self, key: str, timestamp: int) -> str:\n \n\n\n# Your TimeMap object will be instantiated and called as such:\n# obj = TimeMap()\n# obj.set(key,value,timestamp)\n# param_2 = obj.get(key,timestamp)", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "\n\n\ntypedef struct {\n \n} TimeMap;\n\n\nTimeMap* timeMapCreate() {\n \n}\n\nvoid timeMapSet(TimeMap* obj, char * key, char * value, int timestamp) {\n \n}\n\nchar * timeMapGet(TimeMap* obj, char * key, int timestamp) {\n \n}\n\nvoid timeMapFree(TimeMap* obj) {\n \n}\n\n/**\n * Your TimeMap struct will be instantiated and called as such:\n * TimeMap* obj = timeMapCreate();\n * timeMapSet(obj, key, value, timestamp);\n \n * char * param_2 = timeMapGet(obj, key, timestamp);\n \n * timeMapFree(obj);\n*/", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class TimeMap {\n\n public TimeMap() {\n \n }\n \n public void Set(string key, string value, int timestamp) {\n \n }\n \n public string Get(string key, int timestamp) {\n \n }\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * TimeMap obj = new TimeMap();\n * obj.Set(key,value,timestamp);\n * string param_2 = obj.Get(key,timestamp);\n */", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "\nvar TimeMap = function() {\n \n};\n\n/** \n * @param {string} key \n * @param {string} value \n * @param {number} timestamp\n * @return {void}\n */\nTimeMap.prototype.set = function(key, value, timestamp) {\n \n};\n\n/** \n * @param {string} key \n * @param {number} timestamp\n * @return {string}\n */\nTimeMap.prototype.get = function(key, timestamp) {\n \n};\n\n/** \n * Your TimeMap object will be instantiated and called as such:\n * var obj = new TimeMap()\n * obj.set(key,value,timestamp)\n * var param_2 = obj.get(key,timestamp)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "class TimeMap\n def initialize()\n \n end\n\n\n=begin\n :type key: String\n :type value: String\n :type timestamp: Integer\n :rtype: Void\n=end\n def set(key, value, timestamp)\n \n end\n\n\n=begin\n :type key: String\n :type timestamp: Integer\n :rtype: String\n=end\n def get(key, timestamp)\n \n end\n\n\nend\n\n# Your TimeMap object will be instantiated and called as such:\n# obj = TimeMap.new()\n# obj.set(key, value, timestamp)\n# param_2 = obj.get(key, timestamp)", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "\nclass TimeMap {\n\n init() {\n \n }\n \n func set(_ key: String, _ value: String, _ timestamp: Int) {\n \n }\n \n func get(_ key: String, _ timestamp: Int) -> String {\n \n }\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * let obj = TimeMap()\n * obj.set(key, value, timestamp)\n * let ret_2: String = obj.get(key, timestamp)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "type TimeMap struct {\n \n}\n\n\nfunc Constructor() TimeMap {\n \n}\n\n\nfunc (this *TimeMap) Set(key string, value string, timestamp int) {\n \n}\n\n\nfunc (this *TimeMap) Get(key string, timestamp int) string {\n \n}\n\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * obj := Constructor();\n * obj.Set(key,value,timestamp);\n * param_2 := obj.Get(key,timestamp);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "class TimeMap() {\n\n def set(key: String, value: String, timestamp: Int) {\n \n }\n\n def get(key: String, timestamp: Int): String = {\n \n }\n\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * var obj = new TimeMap()\n * obj.set(key,value,timestamp)\n * var param_2 = obj.get(key,timestamp)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Kotlin", "langSlug": "kotlin", "code": "class TimeMap() {\n\n fun set(key: String, value: String, timestamp: Int) {\n \n }\n\n fun get(key: String, timestamp: Int): String {\n \n }\n\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * var obj = TimeMap()\n * obj.set(key,value,timestamp)\n * var param_2 = obj.get(key,timestamp)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Rust", "langSlug": "rust", "code": "struct TimeMap {\n\n}\n\n\n/** \n * `&self` means the method takes an immutable reference.\n * If you need a mutable reference, change it to `&mut self` instead.\n */\nimpl TimeMap {\n\n fn new() -> Self {\n \n }\n \n fn set(&self, key: String, value: String, timestamp: i32) {\n \n }\n \n fn get(&self, key: String, timestamp: i32) -> String {\n \n }\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * let obj = TimeMap::new();\n * obj.set(key, value, timestamp);\n * let ret_2: String = obj.get(key, timestamp);\n */", "__typename": "CodeSnippetNode" }, { "lang": "PHP", "langSlug": "php", "code": "class TimeMap {\n /**\n */\n function __construct() {\n \n }\n \n /**\n * @param String $key\n * @param String $value\n * @param Integer $timestamp\n * @return NULL\n */\n function set($key, $value, $timestamp) {\n \n }\n \n /**\n * @param String $key\n * @param Integer $timestamp\n * @return String\n */\n function get($key, $timestamp) {\n \n }\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * $obj = TimeMap();\n * $obj->set($key, $value, $timestamp);\n * $ret_2 = $obj->get($key, $timestamp);\n */", "__typename": "CodeSnippetNode" }, { "lang": "TypeScript", "langSlug": "typescript", "code": "class TimeMap {\n constructor() {\n\n }\n\n set(key: string, value: string, timestamp: number): void {\n\n }\n\n get(key: string, timestamp: number): string {\n\n }\n}\n\n/**\n * Your TimeMap object will be instantiated and called as such:\n * var obj = new TimeMap()\n * obj.set(key,value,timestamp)\n * var param_2 = obj.get(key,timestamp)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Racket", "langSlug": "racket", "code": "(define time-map%\n (class object%\n (super-new)\n (init-field)\n \n ; set : string? string? exact-integer? -> void?\n (define/public (set key value timestamp)\n\n )\n ; get : string? exact-integer? -> string?\n (define/public (get key timestamp)\n\n )))\n\n;; Your time-map% object will be instantiated and called as such:\n;; (define obj (new time-map%))\n;; (send obj set key value timestamp)\n;; (define param_2 (send obj get key timestamp))", "__typename": "CodeSnippetNode" }, { "lang": "Erlang", "langSlug": "erlang", "code": "-spec time_map_init_() -> any().\ntime_map_init_() ->\n .\n\n-spec time_map_set(Key :: unicode:unicode_binary(), Value :: unicode:unicode_binary(), Timestamp :: integer()) -> any().\ntime_map_set(Key, Value, Timestamp) ->\n .\n\n-spec time_map_get(Key :: unicode:unicode_binary(), Timestamp :: integer()) -> unicode:unicode_binary().\ntime_map_get(Key, Timestamp) ->\n .\n\n\n%% Your functions will be called as such:\n%% time_map_init_(),\n%% time_map_set(Key, Value, Timestamp),\n%% Param_2 = time_map_get(Key, Timestamp),\n\n%% time_map_init_ will be called before every test case, in which you can do some necessary initializations.", "__typename": "CodeSnippetNode" }, { "lang": "Elixir", "langSlug": "elixir", "code": "defmodule TimeMap do\n @spec init_() :: any\n def init_() do\n\n end\n\n @spec set(key :: String.t, value :: 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\\r\\n

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