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Created Jan 18, 2022
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// 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:
function validateCred(array) {
/*We'll place the handled numbers here upon iterating the provided array*/
let iteratedArray = [];
/*Used to determine if iterated number needs doubling*/
let counter = 1;
let digit = 0;
for (let i = array.length - 1; i >= 0; i--) {
/*Counter starts from 1, so last number in array doesn't get doubled*/
if(counter % 2 === 0) {
/*Determining how to handle number after passing "every other digit" test.*/
digit = array[i] * 2 > 9 ? (array[i] * 2) - 9 : array[i] * 2
iteratedArray.unshift(digit);
} else {
iteratedArray.unshift(array[i])
}
counter += 1;
}
//Summing the members of iteratedArray
let sum = iteratedArray.reduce((previousValue, currentValue) => {
return previousValue + currentValue;
});
if (sum % 10 === 0){
return true;
} else {
return false;
}
}
function findInvalidCards(array) {
let invalidCardArray = [];
for (card in array) {
if (validateCred(array[card]) === false){
invalidCardArray.push(array[card]);
}
}
return invalidCardArray;
}
function idInvalidCardCompanies(array) {
let companyArray = [];
//Iterate through invalid cards array
for(card in array) {
let company;
/*First number of card determines company, so assigning company variable according to iterated card*/
switch(array[card][0]) {
case 3:
company = 'Amex (American Express)';
break;
case 4:
company = 'Visa';
break;
case 5:
company = 'Mastercard';
break;
case 6:
company = 'Discover';
break;
default:
company = 'Company not found';
}
//If company is not in companyArray, it gets pushed in
if (companyArray.indexOf(company) === -1) {
companyArray.push(company);
}
}
return companyArray;
}
let invalidCards = findInvalidCards(batch);
console.log(idInvalidCardCompanies(invalidCards));
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