Array practice

arr_pracr.js

'use strict';

// Data
// forEach

const info1 = {
  owner: 'Sita Troy',
  movements: [200, 450, -400, 3000, -650, -130, 70, 1300],
  interestRate: 1.2, // %
  pin: 1111,
};

const info2 = {
  owner: 'Rita Roy',
  movements: [5020, 3400, -150, -790, -3210, -1000, 8500, -30],
  interestRate: 1.5,
  pin: 2222,
};

const info3 = {
  owner: 'Zelda Garfield Fitzgerald',
  movements: [200, -200, 340, -300, -20, 50, 400, -460],
  interestRate: 0.7,
  pin: 3333,
};

const info4 = {
  owner: 'Rusty Shackleton',
  movements: [630, 1000, 700, 50, 90],
  interestRate: 1,
  pin: 4444,
};

const info = [info1, info2, info3, info4];

// 1. sum up money movements

const fakeBankDepositSum = info
  .flatMap(acc => acc.movements)
  .filter(mov => mov > 0)
  .reduce((sum, cur) => sum + cur, 0);

console.log(fakeBankDepositSum);

// 2. count how many deposits => 1000

const fakeNumDeposits1000 = info
  .flatMap(acc => acc.movements)
  .reduce((count, cur) => (cur >= 1000 ? ++count : count), 0);
// .filter(mov => mov >= 1000).length;

console.log(fakeNumDeposits1000);

// 3. advanced reduce method, create an object
// deposits and withdrawals

const { deposits, withdrawals } = info
  .flatMap(acc => acc.movements)
  .reduce(
    (sums, cur) => {
      sums[cur > 0 ? 'deposits' : 'withdrawals'] += cur;
      return sums;
    },
    { deposits: 0, withdrawals: 0 }
  );

console.log(deposits, withdrawals);

// 4. convert string to Title Case: This is a Nice Title

const convertTitleCase = function (title) {
const capitalize = str => str[0].toUpperCase() + str.slice(1);
  const doNotConvert = [
    'a',
    'an',
    'and',
    'the',
    'but',
    'or',
    'on',
    'in',
    'with',
    'is',
  ];

  const titleCase = title
    .toLowerCase()
    .split(' ')
    .map(word => (doNotConvert.includes(word) ? word : capitalize(word)))
    .join(' ');
  return capitalize(titleCase);
};

console.log(convertTitleCase('this is a nice title'));
console.log(convertTitleCase('this is a LONG title but n ot too long'));
console.log(convertTitleCase('and here is another title with an EXAMPLE'));