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"title": "Time Based Key-Value Store",
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"content": "<p>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.</p>\n\n<p>Implement the <code>TimeMap</code> class:</p>\n\n<ul>\n\t<li><code>TimeMap()</code> Initializes the object of the data structure.</li>\n\t<li><code>void set(String key, String value, int timestamp)</code> Stores the key <code>key</code> with the value <code>value </code>at the given time <code>timestamp</code>.</li>\n\t<li><code>String get(String key, int timestamp)</code> Returns a value such that <code>set</code> was called previously, with <code>timestamp_prev <= timestamp</code>. If there are multiple such values, it returns the value associated with the largest <code>timestamp_prev</code>. If there are no values, it returns <code>""</code>.</li>\n</ul>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input</strong>\n["TimeMap", "set", "get", "get", "set", "get", "get"]\n[[], ["foo", "bar", 1], ["foo", 1], ["foo", 3], ["foo", "bar2", 4], ["foo", 4], ["foo", 5]]\n<strong>Output</strong>\n[null, null, "bar", "bar", null, "bar2", "bar2"]\n\n<strong>Explanation</strong>\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</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= key.length, value.length <= 100</code></li>\n\t<li><code>key</code> and <code>value</code> consist of lowercase English letters and digits.</li>\n\t<li><code>1 <= timestamp <= 10<sup>7</sup></code></li>\n\t<li>All the timestamps <code>timestamp</code> of <code>set</code> are strictly increasing.</li>\n\t<li>At most <code>2 * 10<sup>5</sup></code> calls will be made to <code>set</code> and <code>get</code>.</li>\n</ul>\n",
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"lang": "C++",
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"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 */",
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"lang": "Java",
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"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 */",
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"lang": "Python",
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"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)",
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"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)",
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"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*/",
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"lang": "C#",
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"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 */",
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"lang": "JavaScript",
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"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 */",
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"lang": "Ruby",
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"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)",
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"lang": "Swift",
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"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 */",
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"lang": "Go",
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"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 */",
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"lang": "Scala",
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"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 */",
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"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 */",
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"lang": "Rust",
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"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 */",
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"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 */",
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"lang": "TypeScript",
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"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 */",
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"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))",
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"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.",
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"lang": "Elixir",
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"code": "defmodule TimeMap do\n @spec init_() :: any\n def init_() do\n\n end\n\n @spec set(key :: String.t, value :: String.t, timestamp :: integer) :: any\n def set(key, value, timestamp) do\n\n end\n\n @spec get(key :: String.t, timestamp :: integer) :: String.t\n def get(key, timestamp) do\n\n end\nend\n\n# Your functions will be called as such:\n# TimeMap.init_()\n# TimeMap.set(key, value, timestamp)\n# param_2 = TimeMap.get(key, timestamp)\n\n# TimeMap.init_ will be called before every test case, in which you can do some necessary initializations.",
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Java 8 features such as lambda expressions and stream API can be used. </p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>\"], \"python\": [\"Python\", \"<p><code>Python 2.7.12</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/2/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/2/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/2/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. 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For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 8.2</code> using the gnu99 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O1</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n\\r\\n<p>For hash table operations, you may use <a href=\\\"https://troydhanson.github.io/uthash/\\\" target=\\\"_blank\\\">uthash</a>. \\\"uthash.h\\\" is included by default. Below are some examples:</p>\\r\\n\\r\\n<p><b>1. 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