Question about the Cash Register project

JavaScript
1

how is the data in the cash in drawer matched. i don’t quite get it ???

2

Welcome, faalisco.

Would you mind being more specific as to what you do not understand? Are you wanting the tests explained?

The tests can be seen here: freeCodeCamp/cash-register.md at master · freeCodeCamp/freeCodeCamp (github.com)

3

The data is passed as a multidimensional array to the function call, the third argument, each grade (“PENNY”, “NICKEL” etc) has associated a value.

checkCashRegister(19.5, 20, [["PENNY", 1.01], ["NICKEL", 2.05], ["DIME", 3.1], ["QUARTER", 4.25], ["ONE", 90], ["FIVE", 55], ["TEN", 20], ["TWENTY", 60], ["ONE HUNDRED", 100]]);

Then inside the function, the values provided above are mapped against the values contained in the array provided as a base.

var denom = [
    { name: 'ONE HUNDRED', val: 100},
    { name: 'TWENTY', val: 20},
    { name: 'TEN', val: 10},
    { name: 'FIVE', val: 5},
    { name: 'ONE', val: 1},
    { name: 'QUARTER', val: 0.25},
    { name: 'DIME', val: 0.1},
    { name: 'NICKEL', val: 0.05},
    { name: 'PENNY', val: 0.01}
];

As a matter of fact “denom” should be a JavaScript Map https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map rather than an array of objects. (Please do not confuse Array.map method to the Map ) but I suppose that the intention was to keep things simple.

You should think of the checkCashRegister arguments as the state and the “denom” array as a concept, that represents monetary denomination.
(I am sure you know how to use money)

This is what would be materialised in the real world.

Hope this helps.

4

no, what i dont get is the first and the next value in the inner arrays. does the value means thats the total number of the previous value?? e.g [‘penny’, 1.02] means sum of penny is 1.02??

5

yes, there is written that there are 1.02$ in pennies

6