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 = arr => {
let creditCardNum = [];
let cred;
let sum = 0;

for (let i = (arr.length) - 1; i >= 0; i--) {
  if (arr.length % 2 === 1 && i % 2 === 0) {
    creditCardNum.push(arr[i]);
  } else if (arr.length % 2 === 0 && i % 2 === 1) {
    creditCardNum.push(arr[i]);
  } else {
    cred = arr[i] * 2;
    if (cred > 9) {
      cred = cred - 9;
      creditCardNum.push(cred);
    } else {
      creditCardNum.push(cred);
    }
  }
}

//console.log(creditCardNum);

for (const value of creditCardNum) {
  sum += value;
}

//console.log(sum);

if (sum % 10 === 0) {
  return true;
} else {
  return false;
}
}

//console.log(validateCred(invalid5));

const findInvalidCards = arr => {
  let check = true;
  let invalidCards = [];
  for (let k = 0; k < arr.length; k++) {
    check = validateCred(arr[k]);
    if (check === true) {
      continue;
    } else {
      invalidCards.push(arr[k]);
    }
  }
  return invalidCards;  
}

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

let invalidCardBatch = findInvalidCards(batch);
const idInvalidCardCompanies = arr => {
  let invalidCardCompanies = [];
  for (let l = 0; l < arr.length; l++) {
    if (arr[l][0] === 3) {
      invalidCardCompanies.push('Amex (American Express)');
    } else if (arr[l][0] === 4) {
      invalidCardCompanies.push('Visa');
    } else if (arr[l][0] === 5) {
      invalidCardCompanies.push('Mastercard');
    } else if (arr[l][0] === 6) {
      invalidCardCompanies.push('Discover');
    } else {
      console.log('Company not found');
    }
  }

  //console.log(invalidCardCompanies);
  let finalInvalidCardCompanies = [];
  for (let m = 0; m < invalidCardCompanies.length; m++) {
    if (invalidCardCompanies.indexOf(invalidCardCompanies[m]) in finalInvalidCardCompanies) {
      continue;
    } else {
      finalInvalidCardCompanies.push(invalidCardCompanies[m])
    }
    
  }
  //console.log(invalidCardCompanies);
  return finalInvalidCardCompanies;
}

console.log(idInvalidCardCompanies(invalidCardBatch));