{ "data": { "question": { "questionId": "2169", "questionFrontendId": "2043", "boundTopicId": null, "title": "Simple Bank System", "titleSlug": "simple-bank-system", "content": "
You have been tasked with writing a program for a popular bank that will automate all its incoming transactions (transfer, deposit, and withdraw). The bank has n
accounts numbered from 1
to n
. The initial balance of each account is stored in a 0-indexed integer array balance
, with the (i + 1)th
account having an initial balance of balance[i]
.
Execute all the valid transactions. A transaction is valid if:
\n\n1
and n
, andImplement the Bank
class:
Bank(long[] balance)
Initializes the object with the 0-indexed integer array balance
.boolean transfer(int account1, int account2, long money)
Transfers money
dollars from the account numbered account1
to the account numbered account2
. Return true
if the transaction was successful, false
otherwise.boolean deposit(int account, long money)
Deposit money
dollars into the account numbered account
. Return true
if the transaction was successful, false
otherwise.boolean withdraw(int account, long money)
Withdraw money
dollars from the account numbered account
. Return true
if the transaction was successful, false
otherwise.\n
Example 1:
\n\n\nInput\n["Bank", "withdraw", "transfer", "deposit", "transfer", "withdraw"]\n[[[10, 100, 20, 50, 30]], [3, 10], [5, 1, 20], [5, 20], [3, 4, 15], [10, 50]]\nOutput\n[null, true, true, true, false, false]\n\nExplanation\nBank bank = new Bank([10, 100, 20, 50, 30]);\nbank.withdraw(3, 10); // return true, account 3 has a balance of $20, so it is valid to withdraw $10.\n // Account 3 has $20 - $10 = $10.\nbank.transfer(5, 1, 20); // return true, account 5 has a balance of $30, so it is valid to transfer $20.\n // Account 5 has $30 - $20 = $10, and account 1 has $10 + $20 = $30.\nbank.deposit(5, 20); // return true, it is valid to deposit $20 to account 5.\n // Account 5 has $10 + $20 = $30.\nbank.transfer(3, 4, 15); // return false, the current balance of account 3 is $10,\n // so it is invalid to transfer $15 from it.\nbank.withdraw(10, 50); // return false, it is invalid because account 10 does not exist.\n\n\n
\n
Constraints:
\n\nn == balance.length
1 <= n, account, account1, account2 <= 105
0 <= balance[i], money <= 1012
104
calls will be made to each function transfer
, deposit
, withdraw
.Compiled with clang 11
using the latest C++ 20 standard.
Your code is compiled with level two optimization (-O2
). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
\"], \"java\": [\"Java\", \"OpenJDK 17
. Java 8 features such as lambda expressions and stream API can be used.
Most standard library headers are already included automatically for your convenience.
\\r\\nIncludes Pair
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Python 2.7.12
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Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.
\\r\\n\\r\\nFor Map/TreeMap data structure, you may use sortedcontainers library.
\\r\\n\\r\\nNote that Python 2.7 will not be maintained past 2020. For the latest Python, please choose Python3 instead.
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\\r\\n\\r\\nFor hash table operations, you may use uthash. \\\"uthash.h\\\" is included by default. Below are some examples:
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Node.js 16.13.2
.
Your code is run with --harmony
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lodash.js library is included by default.
\\r\\n\\r\\nFor Priority Queue / Queue data structures, you may use 5.3.0 version of datastructures-js/priority-queue and 4.2.1 version of datastructures-js/queue.
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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms
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Go 1.21
Support https://godoc.org/github.com/emirpasic/gods@v1.18.1 library.
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Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.
\\r\\n\\r\\nFor Map/TreeMap data structure, you may use sortedcontainers library.
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Kotlin 1.9.0
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Rust 1.58.1
Supports rand v0.6\\u00a0from crates.io
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With bcmath module
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Dart 2.17.3
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