Cred card checker my solution

https://gist.github.com/5497d594954fb2ef147f6462cb22c140

// 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 = [9, 5, 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 = array => {
let checkModulo = 0;
let vCred = array; // Copies input array
let firstItem = array.pop(); // The first item in the Input array
vCred.reverse(); // Reverses the copied Input array
for (let i = 0; i < vCred.length; i++) { // itrrerates through vCred
if (i % 2 == 0) {
vCred[i] *= 2;
if (vCred [i] > 9) {
vCred[i] -= 9; // Finds all odd numbers, dubbles them. subtracs 9 if they are above 9.
}
}
}
for (let j = 0; j < vCred.length; j++) {
checkModulo += vCred[j];
}
return (checkModulo + firstItem) % 10 === 0;
}
console.log(validateCred(valid1));

// invalid checker

function findInvalidCards(cards) {
let invalidCards = ;

for (let k = 0; k < cards.length; k++) {
if (!validateCred(cards[k])) {
invalidCards.push(cards[k]);
}
}
return invalidCards;
}
//console.log(findInvalidCards(batch));

I stole the last part from someone in here. I found this project really challenging but super fun!

1 Like

Hey,

Unfortunately this will not create a copy, this will only create a reference to the array. Your function will modify the original array.

You would need to chain slice() to the array to really make a copy.

let vCred = array.slice();

What made the last part be so challenging to you?
Looking at how you tackled the first part, the second part should be a piece of cake to you ;).

Happy coding!

Hi! sorry for not replying sooner. ohh i thought that copied. Ill use .slice in the future!
As to why i thought that was so difficult i honestly dont remember :stuck_out_tongue:

happy coding!!

1 Like