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 removeItem = (arr, n) => {
  const newArr = arr.slice();
  newArr.splice(n); 
  return newArr
};

const validateCred = (arr) => {
  let lastItem = arr[arr.length - 1];
  //console.log(arr);
  const newArr = removeItem(arr, arr.length-1);
  //console.log(newArr);
  newArr.reverse();
  //console.log(newArr);
  for (let i = 0; i < newArr.length; i = i+2){
    newArr[i] *= 2;
    if (newArr[i] > 9){
      newArr[i] -= 9;
    }

  };
  //console.log(newArr);
  const arrsum = newArr.reduce((a,b) => {
    return a + b
  });
  //console.log(arrsum + lastItem)

  if ((arrsum + lastItem )% 10 === 0){
    return true;
  }return false

}

console.log(validateCred(valid4));
console.log(validateCred(invalid4));

const findInvalidCards = (nestArr) => {
  let invalidCards =[];
  for(let i = 0; i < nestArr.length; i++){
    const isValid = validateCred(nestArr[i])
    if (!isValid){
      invalidCards.push(nestArr[i]);
    } 
  }
  return invalidCards
};
//console.log (findInvalidCards(batch));

const idInvalidCardCompanies = (invalidArrs) => {
  const compInvalid = [];
  for(let i = 0; i < invalidArrs.length; i++){
    const firstDigit = invalidArrs[i][0];
    if (firstDigit === 3){
      compInvalid.push('Amex')
    }else if(firstDigit === 4){
      compInvalid.push('Visa')
    }else if(firstDigit === 5){
      compInvalid.push('Mastercard')
    }else if(firstDigit ===6){
      compInvalid.push('Discover')
    }else{
      console.log('Company not found')
    }
  }

  //const uniqComp = new Set(compInvalid);
  const uniqComp = compInvalid.filter((comp, pos) => {
    return compInvalid.indexOf(comp) === pos
  })
  return uniqComp
}

const invalidCards = findInvalidCards(batch);
console.log(idInvalidCardCompanies(invalidCards));