Codecademy export

main.js

// All valid credit card numbers
const valid1 = [4, 5, 3, 9, 6, 7, 7, 9, 0, 8, 0, 1, 6, 8, 0, 8];
const valid2 = [5, 5, 3, 5, 7, 6, 6, 7, 6, 8, 7, 5, 1, 4, 3, 9];
const valid3 = [3, 7, 1, 6, 1, 2, 0, 1, 9, 9, 8, 5, 2, 3, 6];
const valid4 = [6, 0, 1, 1, 1, 4, 4, 3, 4, 0, 6, 8, 2, 9, 0, 5];
const valid5 = [4, 5, 3, 9, 4, 0, 4, 9, 6, 7, 8, 6, 9, 6, 6, 6];

// All invalid credit card numbers
const invalid1 = [4, 5, 3, 2, 7, 7, 8, 7, 7, 1, 0, 9, 1, 7, 9, 5];
const invalid2 = [5, 7, 9, 5, 5, 9, 3, 3, 9, 2, 1, 3, 4, 6, 4, 3];
const invalid3 = [3, 7, 5, 7, 9, 6, 0, 8, 4, 4, 5, 9, 9, 1, 4];
const invalid4 = [6, 0, 1, 1, 1, 2, 7, 9, 6, 1, 7, 7, 7, 9, 3, 5];
const invalid5 = [5, 3, 8, 2, 0, 1, 9, 7, 7, 2, 8, 8, 3, 8, 5, 4];

// Can be either valid or invalid
const mystery1 = [3, 4, 4, 8, 0, 1, 9, 6, 8, 3, 0, 5, 4, 1, 4];
const mystery2 = [5, 4, 6, 6, 1, 0, 0, 8, 6, 1, 6, 2, 0, 2, 3, 9];
const mystery3 = [6, 0, 1, 1, 3, 7, 7, 0, 2, 0, 9, 6, 2, 6, 5, 6, 2, 0, 3];
const mystery4 = [4, 9, 2, 9, 8, 7, 7, 1, 6, 9, 2, 1, 7, 0, 9, 3];
const mystery5 = [4, 9, 1, 3, 5, 4, 0, 4, 6, 3, 0, 7, 2, 5, 2, 3];

// An array of all the arrays above
const batch = [valid1, valid2, valid3, valid4, valid5, invalid1, invalid2, invalid3, invalid4, invalid5, mystery1, mystery2, mystery3, mystery4, mystery5];


// Add your functions below:
const validateCred = creditCard => {
  const doubleBelow10 = digit => (digit > 4) ? digit*2 - 9 : digit*2;
  
  let sum = creditCard[creditCard.length - 1];
  let double = true;

  for (let digit = creditCard.length - 2; digit >= 0; digit--) {
    sum += double ? doubleBelow10(creditCard[digit])  : creditCard[digit]; 
    double = !double;
  }

  return sum % 10 === 0;
}

const findInvalidCards = cards => {
  let invalidCards = [];

  for (card = 0; card < cards.length; card++) {
    if (!validateCred(cards[card])) {
      invalidCards.push(cards[card]);
    }
  }

  return invalidCards;
}

const idInvalidCardCompanies = invalidCards => {
  let companies = ['Company not found', 'Company not found',  'Company not found', 'Amex', 'Visa', 'Mastercard', 'Discover', 'Company not found', 'Company not found', 'Company not found' ];
  let faultyCompanies = [];
  
  while (invalidCards.length > 0) {
    let card = invalidCards.pop();
    
    if (!faultyCompanies.includes(companies[card[0]])) {
      faultyCompanies.push(companies[card[0]]);
    }
 /*   switch (card[0]) {
      case 3: 
        if (!companies.includes('Amex')) {
                  companies.push('Amex');
        }
        break;
      case 4: 
        if (!companies.includes('Visa')) {
                  companies.push('Visa');
        }
        break;
      case 5:
        if (!companies.includes('Mastercard')) {
                  companies.push('Mastercard');
        }
        break;
      case 6:
        if (!companies.includes('Discover')) {
                  companies.push('Discover');
        }
        break;
      default: 
        if (!companies.includes('Company not found')) {
                  companies.push('Company not found');
        }
        break;
    } */
  } 

  return faultyCompanies;
}
console.log(findInvalidCards(batch));

console.log(idInvalidCardCompanies(findInvalidCards(batch)));