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
, and500
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 are2
$50
banknotes,1
$100
banknote, and1
$200
banknote, then the machine will use the$100
and$200
banknotes. - However, if you try to withdraw
$600
and there are3
$200
banknotes and1
$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 length5
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 towithdraw
anddeposit
. - At least one call will be made to each function
withdraw
anddeposit
.
- For example, if you want to withdraw
-
-
Constructor Summary
Constructors Constructor Description ATM()
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