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:

// validate single card
function validateCred(card){
    //create a new arr and reverse
    let cardReversed = [...card];
    cardReversed.reverse();

    // calculate sum
    let sum = 0;
    for(let i=0; i<cardReversed.length; i++){
        if(i%2 === 0){
            sum += cardReversed[i];
        }else{
            if(cardReversed[i]*2 > 9){
                sum += cardReversed[i]*2-9;
            }else{
                sum += cardReversed[i]*2;
            }
        }
    }

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

// find invalid cards
function findInvalidCards(cardList){
    let invalidCards = [];
    cardList.forEach(val => {
        if(validateCred(val) === false){
            invalidCards.push(val);
        }
    })
    return invalidCards;
}

// idInvalidCardCompanies
function idInvalidCardCompanies(invalidList){
    let companyIdentifier = [3,4,5,6];
    let digitInvalid = invalidList.map(val => val[0]);
    let companiesInvalid = [];

    // add Company not found
    digitInvalid.forEach(digit => {
        if(companyIdentifier.includes(digit) === false){
            companiesInvalid.push('Company not found');
        }
    })

    // add companies
    if(digitInvalid.includes(3)){
        companiesInvalid.push('Amex');
    }

    if(digitInvalid.includes(4)){
        companiesInvalid.push('Visa');
    }

    if(digitInvalid.includes(5)){
        companiesInvalid.push('Mastercard');
    }

    if(digitInvalid.includes(6)){
        companiesInvalid.push('Discover');
    }
    
    //return result
    return companiesInvalid;
}

//