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"title": "Map Sum Pairs",
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"content": "<p>Design a map that allows you to do the following:</p>\n\n<ul>\n\t<li>Maps a string key to a given value.</li>\n\t<li>Returns the sum of the values that have a key with a prefix equal to a given string.</li>\n</ul>\n\n<p>Implement the <code>MapSum</code> class:</p>\n\n<ul>\n\t<li><code>MapSum()</code> Initializes the <code>MapSum</code> object.</li>\n\t<li><code>void insert(String key, int val)</code> Inserts the <code>key-val</code> pair into the map. If the <code>key</code> already existed, the original <code>key-value</code> pair will be overridden to the new one.</li>\n\t<li><code>int sum(string prefix)</code> Returns the sum of all the pairs' value whose <code>key</code> starts with the <code>prefix</code>.</li>\n</ul>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input</strong>\n["MapSum", "insert", "sum", "insert", "sum"]\n[[], ["apple", 3], ["ap"], ["app", 2], ["ap"]]\n<strong>Output</strong>\n[null, null, 3, null, 5]\n\n<strong>Explanation</strong>\nMapSum mapSum = new MapSum();\nmapSum.insert("apple", 3); \nmapSum.sum("ap"); // return 3 (<u>ap</u>ple = 3)\nmapSum.insert("app", 2); \nmapSum.sum("ap"); // return 5 (<u>ap</u>ple + <u>ap</u>p = 3 + 2 = 5)\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= key.length, prefix.length <= 50</code></li>\n\t<li><code>key</code> and <code>prefix</code> consist of only lowercase English letters.</li>\n\t<li><code>1 <= val <= 1000</code></li>\n\t<li>At most <code>50</code> calls will be made to <code>insert</code> and <code>sum</code>.</li>\n</ul>\n",
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"lang": "C++",
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"code": "class MapSum {\npublic:\n MapSum() {\n \n }\n \n void insert(string key, int val) {\n \n }\n \n int sum(string prefix) {\n \n }\n};\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * MapSum* obj = new MapSum();\n * obj->insert(key,val);\n * int param_2 = obj->sum(prefix);\n */",
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"lang": "Java",
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"code": "class MapSum {\n\n public MapSum() {\n \n }\n \n public void insert(String key, int val) {\n \n }\n \n public int sum(String prefix) {\n \n }\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * MapSum obj = new MapSum();\n * obj.insert(key,val);\n * int param_2 = obj.sum(prefix);\n */",
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"lang": "Python",
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"code": "class MapSum(object):\n\n def __init__(self):\n \n\n def insert(self, key, val):\n \"\"\"\n :type key: str\n :type val: int\n :rtype: None\n \"\"\"\n \n\n def sum(self, prefix):\n \"\"\"\n :type prefix: str\n :rtype: int\n \"\"\"\n \n\n\n# Your MapSum object will be instantiated and called as such:\n# obj = MapSum()\n# obj.insert(key,val)\n# param_2 = obj.sum(prefix)",
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"code": "class MapSum:\n\n def __init__(self):\n \n\n def insert(self, key: str, val: int) -> None:\n \n\n def sum(self, prefix: str) -> int:\n \n\n\n# Your MapSum object will be instantiated and called as such:\n# obj = MapSum()\n# obj.insert(key,val)\n# param_2 = obj.sum(prefix)",
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"lang": "C",
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"code": "\n\n\ntypedef struct {\n \n} MapSum;\n\n\nMapSum* mapSumCreate() {\n \n}\n\nvoid mapSumInsert(MapSum* obj, char * key, int val) {\n \n}\n\nint mapSumSum(MapSum* obj, char * prefix) {\n \n}\n\nvoid mapSumFree(MapSum* obj) {\n \n}\n\n/**\n * Your MapSum struct will be instantiated and called as such:\n * MapSum* obj = mapSumCreate();\n * mapSumInsert(obj, key, val);\n \n * int param_2 = mapSumSum(obj, prefix);\n \n * mapSumFree(obj);\n*/",
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"lang": "C#",
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"code": "public class MapSum {\n\n public MapSum() {\n \n }\n \n public void Insert(string key, int val) {\n \n }\n \n public int Sum(string prefix) {\n \n }\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * MapSum obj = new MapSum();\n * obj.Insert(key,val);\n * int param_2 = obj.Sum(prefix);\n */",
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"lang": "JavaScript",
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"code": "\nvar MapSum = function() {\n \n};\n\n/** \n * @param {string} key \n * @param {number} val\n * @return {void}\n */\nMapSum.prototype.insert = function(key, val) {\n \n};\n\n/** \n * @param {string} prefix\n * @return {number}\n */\nMapSum.prototype.sum = function(prefix) {\n \n};\n\n/** \n * Your MapSum object will be instantiated and called as such:\n * var obj = new MapSum()\n * obj.insert(key,val)\n * var param_2 = obj.sum(prefix)\n */",
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"lang": "Ruby",
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"code": "class MapSum\n def initialize()\n \n end\n\n\n=begin\n :type key: String\n :type val: Integer\n :rtype: Void\n=end\n def insert(key, val)\n \n end\n\n\n=begin\n :type prefix: String\n :rtype: Integer\n=end\n def sum(prefix)\n \n end\n\n\nend\n\n# Your MapSum object will be instantiated and called as such:\n# obj = MapSum.new()\n# obj.insert(key, val)\n# param_2 = obj.sum(prefix)",
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"lang": "Swift",
"langSlug": "swift",
"code": "\nclass MapSum {\n\n init() {\n \n }\n \n func insert(_ key: String, _ val: Int) {\n \n }\n \n func sum(_ prefix: String) -> Int {\n \n }\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * let obj = MapSum()\n * obj.insert(key, val)\n * let ret_2: Int = obj.sum(prefix)\n */",
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"lang": "Go",
"langSlug": "golang",
"code": "type MapSum struct {\n \n}\n\n\nfunc Constructor() MapSum {\n \n}\n\n\nfunc (this *MapSum) Insert(key string, val int) {\n \n}\n\n\nfunc (this *MapSum) Sum(prefix string) int {\n \n}\n\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * obj := Constructor();\n * obj.Insert(key,val);\n * param_2 := obj.Sum(prefix);\n */",
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"lang": "Scala",
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"code": "class MapSum() {\n\n def insert(key: String, `val`: Int) {\n \n }\n\n def sum(prefix: String): Int = {\n \n }\n\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * var obj = new MapSum()\n * obj.insert(key,`val`)\n * var param_2 = obj.sum(prefix)\n */",
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"lang": "Kotlin",
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"code": "class MapSum() {\n\n fun insert(key: String, `val`: Int) {\n \n }\n\n fun sum(prefix: String): Int {\n \n }\n\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * var obj = MapSum()\n * obj.insert(key,`val`)\n * var param_2 = obj.sum(prefix)\n */",
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"lang": "Rust",
"langSlug": "rust",
"code": "struct MapSum {\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 MapSum {\n\n fn new() -> Self {\n \n }\n \n fn insert(&self, key: String, val: i32) {\n \n }\n \n fn sum(&self, prefix: String) -> i32 {\n \n }\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * let obj = MapSum::new();\n * obj.insert(key, val);\n * let ret_2: i32 = obj.sum(prefix);\n */",
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"lang": "PHP",
"langSlug": "php",
"code": "class MapSum {\n /**\n */\n function __construct() {\n \n }\n \n /**\n * @param String $key\n * @param Integer $val\n * @return NULL\n */\n function insert($key, $val) {\n \n }\n \n /**\n * @param String $prefix\n * @return Integer\n */\n function sum($prefix) {\n \n }\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * $obj = MapSum();\n * $obj->insert($key, $val);\n * $ret_2 = $obj->sum($prefix);\n */",
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"lang": "TypeScript",
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"code": "class MapSum {\n constructor() {\n\n }\n\n insert(key: string, val: number): void {\n\n }\n\n sum(prefix: string): number {\n\n }\n}\n\n/**\n * Your MapSum object will be instantiated and called as such:\n * var obj = new MapSum()\n * obj.insert(key,val)\n * var param_2 = obj.sum(prefix)\n */",
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"code": "(define map-sum%\n (class object%\n (super-new)\n (init-field)\n \n ; insert : string? exact-integer? -> void?\n (define/public (insert key val)\n\n )\n ; sum : string? -> exact-integer?\n (define/public (sum prefix)\n\n )))\n\n;; Your map-sum% object will be instantiated and called as such:\n;; (define obj (new map-sum%))\n;; (send obj insert key val)\n;; (define param_2 (send obj sum prefix))",
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"code": "-spec map_sum_init_() -> any().\nmap_sum_init_() ->\n .\n\n-spec map_sum_insert(Key :: unicode:unicode_binary(), Val :: integer()) -> any().\nmap_sum_insert(Key, Val) ->\n .\n\n-spec map_sum_sum(Prefix :: unicode:unicode_binary()) -> integer().\nmap_sum_sum(Prefix) ->\n .\n\n\n%% Your functions will be called as such:\n%% map_sum_init_(),\n%% map_sum_insert(Key, Val),\n%% Param_2 = map_sum_sum(Prefix),\n\n%% map_sum_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 MapSum do\n @spec init_() :: any\n def init_() do\n\n end\n\n @spec insert(key :: String.t, val :: integer) :: any\n def insert(key, val) do\n\n end\n\n @spec sum(prefix :: String.t) :: integer\n def sum(prefix) do\n\n end\nend\n\n# Your functions will be called as such:\n# MapSum.init_()\n# MapSum.insert(key, val)\n# param_2 = MapSum.sum(prefix)\n\n# MapSum.init_ will be called before every test case, in which you can do some necessary initializations.",
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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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