flat_and_flatMap_methods.js

'use strict';
// Data
const account1 = {
    owner: 'Jonas Schmedtmann',
    movements: [200, 450, -400, 3000, -650, -130, 70, 1300],
    interestRate: 1.2, // %
    pin: 1111,
  };
  
  const account2 = {
    owner: 'Jessica Davis',
    movements: [5000, 3400, -150, -790, -3210, -1000, 8500, -30],
    interestRate: 1.5,
    pin: 2222,
  };
  
  const account3 = {
    owner: 'Steven Thomas Williams',
    movements: [200, -200, 340, -300, -20, 50, 400, -460],
    interestRate: 0.7,
    pin: 3333,
  };
  
  const account4 = {
    owner: 'Sarah Smith',
    movements: [430, 1000, 700, 50, 90],
    interestRate: 1,
    pin: 4444,
  };

const accounts = [account1, account2, account3, account4];

//Task is that we can find the total current amount in the bank

/**********Flat Method********/
const totalBankAmount=accounts
   .map(acc => acc.movements)
   .flat(1)
   .reduce((acc,mov) => acc+mov,0);
console.log(totalBankAmount);

/**********FlatMap Method********/
const bankTotalAmount=accounts.flatMap(acc => acc.movements).reduce((acc,mov) => acc+mov,0);
console.log(bankTotalAmount);