{ "data": { "question": { "questionId": "2352", "questionFrontendId": "2241", "boundTopicId": null, "title": "Design an ATM Machine", "titleSlug": "design-an-atm-machine", "content": "

There is an ATM machine that stores banknotes of 5 denominations: 20, 50, 100, 200, and 500 dollars. Initially the ATM is empty. The user can use the machine to deposit or withdraw any amount of money.

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When withdrawing, the machine prioritizes using banknotes of larger values.

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Implement the ATM class:

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Example 1:

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\nInput\n["ATM", "deposit", "withdraw", "deposit", "withdraw", "withdraw"]\n[[], [[0,0,1,2,1]], [600], [[0,1,0,1,1]], [600], [550]]\nOutput\n[null, null, [0,0,1,0,1], null, [-1], [0,1,0,0,1]]\n\nExplanation\nATM atm = new ATM();\natm.deposit([0,0,1,2,1]); // Deposits 1 $100 banknote, 2 $200 banknotes,\n                          // and 1 $500 banknote.\natm.withdraw(600);        // Returns [0,0,1,0,1]. The machine uses 1 $100 banknote\n                          // and 1 $500 banknote. The banknotes left over in the\n                          // machine are [0,0,0,2,0].\natm.deposit([0,1,0,1,1]); // Deposits 1 $50, $200, and $500 banknote.\n                          // The banknotes in the machine are now [0,1,0,3,1].\natm.withdraw(600);        // Returns [-1]. The machine will try to use a $500 banknote\n                          // and then be unable to complete the remaining $100,\n                          // so the withdraw request will be rejected.\n                          // Since the request is rejected, the number of banknotes\n                          // in the machine is not modified.\natm.withdraw(550);        // Returns [0,1,0,0,1]. The machine uses 1 $50 banknote\n                          // and 1 $500 banknote.
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Constraints:

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"companyTagStats": null, "codeSnippets": [ { "lang": "C++", "langSlug": "cpp", "code": "class ATM {\npublic:\n ATM() {\n \n }\n \n void deposit(vector banknotesCount) {\n \n }\n \n vector withdraw(int amount) {\n \n }\n};\n\n/**\n * Your ATM object will be instantiated and called as such:\n * ATM* obj = new ATM();\n * obj->deposit(banknotesCount);\n * vector param_2 = obj->withdraw(amount);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Java", "langSlug": "java", "code": "class ATM {\n\n public ATM() {\n \n }\n \n public void deposit(int[] banknotesCount) {\n \n }\n \n public int[] withdraw(int amount) {\n \n }\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * ATM obj = new ATM();\n * obj.deposit(banknotesCount);\n * int[] param_2 = obj.withdraw(amount);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Python", "langSlug": "python", "code": "class ATM(object):\n\n def __init__(self):\n \n\n def deposit(self, banknotesCount):\n \"\"\"\n :type banknotesCount: List[int]\n :rtype: None\n \"\"\"\n \n\n def withdraw(self, amount):\n \"\"\"\n :type amount: int\n :rtype: List[int]\n \"\"\"\n \n\n\n# Your ATM object will be instantiated and called as such:\n# obj = ATM()\n# obj.deposit(banknotesCount)\n# param_2 = obj.withdraw(amount)", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "class ATM:\n\n def __init__(self):\n \n\n def deposit(self, banknotesCount: List[int]) -> None:\n \n\n def withdraw(self, amount: int) -> List[int]:\n \n\n\n# Your ATM object will be instantiated and called as such:\n# obj = ATM()\n# obj.deposit(banknotesCount)\n# param_2 = obj.withdraw(amount)", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "\n\n\ntypedef struct {\n \n} ATM;\n\n\nATM* aTMCreate() {\n \n}\n\nvoid aTMDeposit(ATM* obj, int* banknotesCount, int banknotesCountSize) {\n \n}\n\nint* aTMWithdraw(ATM* obj, int amount, int* retSize) {\n \n}\n\nvoid aTMFree(ATM* obj) {\n \n}\n\n/**\n * Your ATM struct will be instantiated and called as such:\n * ATM* obj = aTMCreate();\n * aTMDeposit(obj, banknotesCount, banknotesCountSize);\n \n * int* param_2 = aTMWithdraw(obj, amount, retSize);\n \n * aTMFree(obj);\n*/", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class ATM {\n\n public ATM() {\n \n }\n \n public void Deposit(int[] banknotesCount) {\n \n }\n \n public int[] Withdraw(int amount) {\n \n }\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * ATM obj = new ATM();\n * obj.Deposit(banknotesCount);\n * int[] param_2 = obj.Withdraw(amount);\n */", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "\nvar ATM = function() {\n \n};\n\n/** \n * @param {number[]} banknotesCount\n * @return {void}\n */\nATM.prototype.deposit = function(banknotesCount) {\n \n};\n\n/** \n * @param {number} amount\n * @return {number[]}\n */\nATM.prototype.withdraw = function(amount) {\n \n};\n\n/** \n * Your ATM object will be instantiated and called as such:\n * var obj = new ATM()\n * obj.deposit(banknotesCount)\n * var param_2 = obj.withdraw(amount)\n */", "__typename": "CodeSnippetNode" }, { "lang": "TypeScript", "langSlug": "typescript", "code": "class ATM {\n constructor() {\n \n }\n\n deposit(banknotesCount: number[]): void {\n \n }\n\n withdraw(amount: number): number[] {\n \n }\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * var obj = new ATM()\n * obj.deposit(banknotesCount)\n * var param_2 = obj.withdraw(amount)\n */", "__typename": "CodeSnippetNode" }, { "lang": "PHP", "langSlug": "php", "code": "class ATM {\n /**\n */\n function __construct() {\n \n }\n \n /**\n * @param Integer[] $banknotesCount\n * @return NULL\n */\n function deposit($banknotesCount) {\n \n }\n \n /**\n * @param Integer $amount\n * @return Integer[]\n */\n function withdraw($amount) {\n \n }\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * $obj = ATM();\n * $obj->deposit($banknotesCount);\n * $ret_2 = $obj->withdraw($amount);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "\nclass ATM {\n\n init() {\n \n }\n \n func deposit(_ banknotesCount: [Int]) {\n \n }\n \n func withdraw(_ amount: Int) -> [Int] {\n \n }\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * let obj = ATM()\n * obj.deposit(banknotesCount)\n * let ret_2: [Int] = obj.withdraw(amount)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Kotlin", "langSlug": "kotlin", "code": "class ATM() {\n\n fun deposit(banknotesCount: IntArray) {\n \n }\n\n fun withdraw(amount: Int): IntArray {\n \n }\n\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * var obj = ATM()\n * obj.deposit(banknotesCount)\n * var param_2 = obj.withdraw(amount)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Dart", "langSlug": "dart", "code": "class ATM {\n\n ATM() {\n \n }\n \n void deposit(List banknotesCount) {\n \n }\n \n List withdraw(int amount) {\n \n }\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * ATM obj = ATM();\n * obj.deposit(banknotesCount);\n * List param2 = obj.withdraw(amount);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "type ATM struct {\n \n}\n\n\nfunc Constructor() ATM {\n \n}\n\n\nfunc (this *ATM) Deposit(banknotesCount []int) {\n \n}\n\n\nfunc (this *ATM) Withdraw(amount int) []int {\n \n}\n\n\n/**\n * Your ATM object will be instantiated and called as such:\n * obj := Constructor();\n * obj.Deposit(banknotesCount);\n * param_2 := obj.Withdraw(amount);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "class ATM\n def initialize()\n \n end\n\n\n=begin\n :type banknotes_count: Integer[]\n :rtype: Void\n=end\n def deposit(banknotes_count)\n \n end\n\n\n=begin\n :type amount: Integer\n :rtype: Integer[]\n=end\n def withdraw(amount)\n \n end\n\n\nend\n\n# Your ATM object will be instantiated and called as such:\n# obj = ATM.new()\n# obj.deposit(banknotes_count)\n# param_2 = obj.withdraw(amount)", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "class ATM() {\n\n def deposit(banknotesCount: Array[Int]) {\n \n }\n\n def withdraw(amount: Int): Array[Int] = {\n \n }\n\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * var obj = new ATM()\n * obj.deposit(banknotesCount)\n * var param_2 = obj.withdraw(amount)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Rust", "langSlug": "rust", "code": "struct ATM {\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 ATM {\n\n fn new() -> Self {\n \n }\n \n fn deposit(&self, banknotes_count: Vec) {\n \n }\n \n fn withdraw(&self, amount: i32) -> Vec {\n \n }\n}\n\n/**\n * Your ATM object will be instantiated and called as such:\n * let obj = ATM::new();\n * obj.deposit(banknotesCount);\n * let ret_2: Vec = obj.withdraw(amount);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Racket", "langSlug": "racket", "code": "(define atm%\n (class object%\n (super-new)\n \n (init-field)\n \n ; deposit : (listof exact-integer?) -> void?\n (define/public (deposit banknotes-count)\n )\n ; withdraw : exact-integer? -> (listof exact-integer?)\n (define/public (withdraw amount)\n )))\n\n;; Your atm% object will be instantiated and called as such:\n;; (define obj (new atm%))\n;; (send obj deposit banknotes-count)\n;; (define param_2 (send obj withdraw amount))", "__typename": "CodeSnippetNode" }, { "lang": "Erlang", "langSlug": "erlang", "code": "-spec atm_init_() -> any().\natm_init_() ->\n .\n\n-spec atm_deposit(BanknotesCount :: [integer()]) -> any().\natm_deposit(BanknotesCount) ->\n .\n\n-spec atm_withdraw(Amount :: integer()) -> [integer()].\natm_withdraw(Amount) ->\n .\n\n\n%% Your functions will be called as such:\n%% atm_init_(),\n%% atm_deposit(BanknotesCount),\n%% Param_2 = atm_withdraw(Amount),\n\n%% atm_init_ will be called before every test case, in which you can do some necessary initializations.", "__typename": "CodeSnippetNode" }, { "lang": "Elixir", "langSlug": "elixir", "code": "defmodule ATM do\n @spec init_() :: any\n def init_() do\n \n end\n\n @spec deposit(banknotes_count :: [integer]) :: any\n def deposit(banknotes_count) do\n \n end\n\n @spec withdraw(amount :: integer) :: [integer]\n def withdraw(amount) do\n \n end\nend\n\n# Your functions will be called as such:\n# ATM.init_()\n# ATM.deposit(banknotes_count)\n# param_2 = ATM.withdraw(amount)\n\n# ATM.init_ will be called before every test case, in which you can do some necessary initializations.", "__typename": "CodeSnippetNode" } ], "stats": "{\"totalAccepted\": \"17.3K\", \"totalSubmission\": \"43.8K\", \"totalAcceptedRaw\": 17343, \"totalSubmissionRaw\": 43767, \"acRate\": \"39.6%\"}", 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