2043. Simple Bank System

# 2043. Simple Bank System#

## 题目 #

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:

• The given account number(s) are between 1 and n, and
• The amount of money withdrawn or transferred from is less than or equal to the balance of the account.

Implement 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.

Example 1:

``````Input
["Bank", "withdraw", "transfer", "deposit", "transfer", "withdraw"]
[[[10, 100, 20, 50, 30]], [3, 10], [5, 1, 20], [5, 20], [3, 4, 15], [10, 50]]
Output
[null, true, true, true, false, false]

Explanation
Bank bank = new Bank([10, 100, 20, 50, 30]);
bank.withdraw(3, 10);    // return true, account 3 has a balance of \$20, so it is valid to withdraw \$10.
// Account 3 has \$20 - \$10 = \$10.
bank.transfer(5, 1, 20); // return true, account 5 has a balance of \$30, so it is valid to transfer \$20.
// Account 5 has \$30 - \$20 = \$10, and account 1 has \$10 + \$20 = \$30.
bank.deposit(5, 20);     // return true, it is valid to deposit \$20 to account 5.
// Account 5 has \$10 + \$20 = \$30.
bank.transfer(3, 4, 15); // return false, the current balance of account 3 is \$10,
// so it is invalid to transfer \$15 from it.
bank.withdraw(10, 50);   // return false, it is invalid because account 10 does not exist.
``````

Constraints:

• n == balance.length
• 1 <= n, account, account1, account2 <= 100000
• 0 <= balance[i], money <= 1000000000000
• At most 104 calls will be made to each function transfer, deposit, withdraw.

## 题目大意 #

• 指定的账户数量在 1 和 n 之间，且
• 取款或者转账需要的钱的总数 小于或者等于 账户余额。

• Bank(long[] balance) 使用下标从 0 开始的整数数组 balance 初始化该对象。
• boolean transfer(int account1, int account2, long money) 从编号为 account1 的账户向编号为 account2 的账户转帐 money 美元。如果交易成功，返回 true ，否则，返回 false 。
• boolean deposit(int account, long money) 向编号为 account 的账户存款 money 美元。如果交易成功，返回 true ；否则，返回 false 。
• boolean withdraw(int account, long money) 从编号为 account 的账户取款 money 美元。如果交易成功，返回 true ；否则，返回 false 。

## 解题思路 #

``````根据题意进行简单模拟
``````

# 代码 #

``````package leetcode

type Bank struct {
accounts []int64
n        int
}

func Constructor(balance []int64) Bank {
return Bank{
accounts: balance,
n:        len(balance),
}
}

func (this *Bank) Transfer(account1 int, account2 int, money int64) bool {
if account1 > this.n || account2 > this.n {
return false
}
if this.accounts[account1-1] < money {
return false
}
this.accounts[account1-1] -= money
this.accounts[account2-1] += money
return true
}

func (this *Bank) Deposit(account int, money int64) bool {
if account > this.n {
return false
}
this.accounts[account-1] += money
return true
}

func (this *Bank) Withdraw(account int, money int64) bool {
if account > this.n {
return false
}
if this.accounts[account-1] < money {
return false
}
this.accounts[account-1] -= money
return true
}
`````` Jun 22, 2022 Edit this page