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:
/* 2.Create a function, validateCred() that has a parameter of an array. The purpose of validateCred() is to return true when an array contains digits of a valid credit card number and false.Also,  use the Luhn algorithm.  */
function validateCred(arrCard) {
  let newArrCar = arrCard.reverse();
  let sum = 0;
  for (let i = 0; i < newArrCar.length; i++) {
    if ((i + 2) % 2 === 0) {
      sum = sum + arrCard[i];
      //console.log(`Position:${i + 1}`, arrCard[i], "sum:", sum);
    }
    if ((i + 2) % 2 !== 0) {
      arrCard[i] * 2 < 9
        ? (sum += arrCard[i] * 2)
        : (sum += arrCard[i] * 2 - 9);
      //console.log(`Position: ${i + 1}`,"number: " + arrCard[i],arrCard[i] * 2 > 9,"sum",sum);
    }
  }
  //console.log("suma", sum);
  return sum % 10 === 0 ? true : false;
}
//console.log(validateCred(valid1));
//console.log(validateCred(invalid1));

/*3.The role of findInvalidCards() is to check through the nested array for which numbers are invalid, and return another nested array of invalid cards.*/
function findInvalidCards(arrCards) {
  let invalidCards = [];
  //using for...of
  for (let card of arrCards) {
    if (validateCred(card) === false) {
      invalidCards.push(card);
    }
  }
  return invalidCards;
}
findInvalidCards(batch);
//console.log("Invalids cards:", "\n", findInvalidCards(batch));

/*4. After finding all the invalid credit card numbers, it’s also necessary to identify the credit card companies that have possibly issued these faulty numbers.*/
let invalidCards = findInvalidCards(batch);
//console.log("Invalids cards:", "\n", invalidCards);
function idInvalidCardCompanies(invalidCards) {
  console.log("bad Cards", "\n", invalidCards);
  let badCardCompanies = [];
  for (let card of invalidCards) {
    //console.log("id bad Card",card[0]);
    switch (true) {
      case 3 === card[0]:
        badCardCompanies.push("Amex (American Express)");
        break;
      case 4 === card[0]:
        badCardCompanies.push("Visa");
        break;
      case 5 === card[0]:
        badCardCompanies.push("Mastercard");
        break;
      case 6 === card[0]:
        badCardCompanies.push("Discover");
        break;
      default:
        badCardCompanies.push("Company not found");
    }
  }
  //console.log(badCardCompanies);
  //------delete duplicates
  badCardCompanies = [...new Set(badCardCompanies )];
  return  badCardCompanies;
}

console.log(
  "Companies that have issued:",
  "\n",
  idInvalidCardCompanies(invalidCards)
);