Package g2201_2300.s2241_design_an_atm_machine

Class ATM

java.lang.Object
g2201_2300.s2241_design_an_atm_machine.ATM
public class ATM extends Object
2241 - Design an ATM Machine\. Medium 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. When withdrawing, the machine prioritizes using banknotes of **larger** values. * For example, if you want to withdraw `$300` and there are `2` `$50` banknotes, `1` `$100` banknote, and `1` `$200` banknote, then the machine will use the `$100` and `$200` banknotes. * However, if you try to withdraw `$600` and there are `3` `$200` banknotes and `1` `$500` banknote, then the withdraw request will be rejected because the machine will first try to use the `$500` banknote and then be unable to use banknotes to complete the remaining `$100`. Note that the machine is **not** allowed to use the `$200` banknotes instead of the `$500` banknote. Implement the ATM class: * `ATM()` Initializes the ATM object. * `void deposit(int[] banknotesCount)` Deposits new banknotes in the order `$20`, `$50`, `$100`, `$200`, and `$500`. * `int[] withdraw(int amount)` Returns an array of length `5` of the number of banknotes that will be handed to the user in the order `$20`, `$50`, `$100`, `$200`, and `$500`, and update the number of banknotes in the ATM after withdrawing. Returns `[-1]` if it is not possible (do **not** withdraw any banknotes in this case). **Example 1:** **Input** ["ATM", "deposit", "withdraw", "deposit", "withdraw", "withdraw"] [ [], [[0,0,1,2,1]], [600], [[0,1,0,1,1]], [600], [550]] **Output:** [null, null, [0,0,1,0,1], null, [-1], [0,1,0,0,1]] **Explanation:** ATM atm = new ATM(); atm.deposit([0,0,1,2,1]); // Deposits 1 $100 banknote, 2 $200 banknotes, // and 1 $500 banknote. atm.withdraw(600); // Returns [0,0,1,0,1]. The machine uses 1 $100 banknote // and 1 $500 banknote. The banknotes left over in the // machine are [0,0,0,2,0]. atm.deposit([0,1,0,1,1]); // Deposits 1 $50, $200, and $500 banknote. // The banknotes in the machine are now [0,1,0,3,1]. atm.withdraw(600); // Returns [-1]. The machine will try to use a $500 banknote // and then be unable to complete the remaining $100, // so the withdraw request will be rejected. // Since the request is rejected, the number of banknotes // in the machine is not modified. atm.withdraw(550); // Returns [0,1,0,0,1]. The machine uses 1 $50 banknote // and 1 $500 banknote. **Constraints:** * `banknotesCount.length == 5` * 0 <= banknotesCount[i] <= 109 * 1 <= amount <= 109 * At most `5000` calls **in total** will be made to `withdraw` and `deposit`. * At least **one** call will be made to each function `withdraw` and `deposit`.

  • Constructor Details

    • ATM

      public ATM()

  • Method Details

    • deposit

      public void deposit(int[] banknotesCount)

    • withdraw

      public int[] withdraw(int amount)