2043-SimpleBankSystem.go

package main

// 2043. Simple Bank System
// 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//     The amount of money withdrawn or transferred from is less than or equal to the balance of the account.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 <= 10^5
//     0 <= balance[i], money <= 10^12
//     At most 10^4 calls will be made to each function transfer, deposit, withdraw.

import "fmt"

type Bank struct {
    Accounts []int64
}

func Constructor(balance []int64) Bank {
    return Bank{ balance }
}

func (this *Bank) Transfer(account1 int, account2 int, money int64) bool {
    if len(this.Accounts) < account1 || len(this.Accounts) < account2 { // 检查帐号是否在账户范围内
        return false
    }
    if this.Accounts[account1 - 1] < money { return false } // 查看 account1 帐号余额是否足够
    this.Accounts[account1-1] -= money
    this.Accounts[account2-1] += money
    return true
}

func (this *Bank) Deposit(account int, money int64) bool {
    if len(this.Accounts) < account { return false } // 检查帐号是否在账户范围内
    this.Accounts[account-1] += money
    return true
}

func (this *Bank) Withdraw(account int, money int64) bool {
    if len(this.Accounts) < account { return false } // 检查帐号是否在账户范围内
    if this.Accounts[account-1] < money { return false } // 查看 account 帐号余额是否足够
    this.Accounts[account-1] -= money
    return true
}

/**
 * Your Bank object will be instantiated and called as such:
 * obj := Constructor(balance);
 * param_1 := obj.Transfer(account1,account2,money);
 * param_2 := obj.Deposit(account,money);
 * param_3 := obj.Withdraw(account,money);
 */

func main() {
    // Bank bank = new Bank([10, 100, 20, 50, 30]);
    obj := Constructor([]int64{10, 100, 20, 50, 30})
    fmt.Println(obj)
    // 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.
    fmt.Println(obj.Withdraw(3, 10)) // true
    fmt.Println(obj)
    // 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.
    fmt.Println(obj.Transfer(5, 1, 20)) // true
    fmt.Println(obj)
    // bank.deposit(5, 20);     // return true, it is valid to deposit $20 to account 5.
    //                          // Account 5 has $10 + $20 = $30.
    fmt.Println(obj.Deposit(5, 20)) // true
    fmt.Println(obj)
    // bank.transfer(3, 4, 15); // return false, the current balance of account 3 is $10,
    //                          // so it is invalid to transfer $15 from it.
    fmt.Println(obj.Transfer(3, 4, 15)) // false
    fmt.Println(obj)
    // bank.withdraw(10, 50);   // return false, it is invalid because account 10 does not exist.
    fmt.Println(obj.Withdraw(10, 15)) // false
    fmt.Println(obj)
}