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-inde

Bank.js

/**
 * Bank constructor initializes the bank with account balances.
 * @param {number[]} balance - Array of initial balances for each account (1-indexed).
 */
var Bank = function(balance) {
  // Create an array of accounts with an extra slot at index 0 (unused).
  // This allows 1-based indexing for accounts.
  this.accounts = Array.from({ length: balance.length + 1 }, (_, i) => balance[i - 1] ?? 0);
  
  // Store the total number of accounts including the unused 0th index.
  this.size = balance.length + 1;
};

/** 
 * Transfers money from one account to another.
 * @param {number} account1 - Source account number (1-indexed).
 * @param {number} account2 - Destination account number (1-indexed).
 * @param {number} money - Amount to transfer.
 * @return {boolean} - Returns true if transfer is successful, false otherwise.
 */
Bank.prototype.transfer = function(account1, account2, money) {
  // Validate account numbers are within bounds.
  if (account1 < 1 || account1 >= this.size || account2 < 1 || account2 >= this.size) return false;

  // Check if the source account has enough funds.
  if (this.accounts[account1] < money) return false;

  // Perform the transfer.
  this.accounts[account1] -= money;
  this.accounts[account2] += money;
  return true;
};

/** 
 * Deposits money into an account.
 * @param {number} account - Account number (1-indexed).
 * @param {number} money - Amount to deposit.
 * @return {boolean} - Returns true if deposit is successful, false otherwise.
 */
Bank.prototype.deposit = function(account, money) {
  // Validate account number.
  if (account < 1 || account >= this.size) return false;

  // Add money to the account.
  this.accounts[account] += money;
  return true;
};

/** 
 * Withdraws money from an account.
 * @param {number} account - Account number (1-indexed).
 * @param {number} money - Amount to withdraw.
 * @return {boolean} - Returns true if withdrawal is successful, false otherwise.
 */
Bank.prototype.withdraw = function(account, money) {
  // Validate account number.
  if (account < 1 || account >= this.size) return false;

  // Check if the account has enough funds.
  if (this.accounts[account] < money) return false;

  // Deduct money from the account.
  this.accounts[account] -= money;
  return true;
};

/** 
 * Your Bank object will be instantiated and called as such:
 * var obj = new Bank(balance)
 * var param_1 = obj.transfer(account1,account2,money)
 * var param_2 = obj.deposit(account,money)
 * var param_3 = obj.withdraw(account,money)
 */