Build A Cash Register

JavaScript
1

My code works for everything until I input a “cash” value that is greater than 37. I don’t understand why that specific value and I have looked for mistakes in the code, but as I said it works for all but one test check. The code runs correctly but not the if statement in the purchase function at a value greater than 37. Any guidance is appreciated!

let price = 1.87;
let cid = [
  ['PENNY', 1.01],
  ['NICKEL', 2.05],
  ['DIME', 3.1],
  ['QUARTER', 4.25],
  ['ONE', 90],
  ['FIVE', 55],
  ['TEN', 20],
  ['TWENTY', 60],
  ['ONE HUNDRED', 100]
];

const currencyUnits = [
  ['PENNY', 0.01],
  ['NICKEL', 0.05],
  ['DIME', 0.1],
  ['QUARTER', 0.25],
  ['ONE', 1],
  ['FIVE', 5],
  ['TEN', 10],
  ['TWENTY', 20],
  ['ONE HUNDRED', 100]
];

const changeDueElement = document.getElementById("change-due");
const cash = document.getElementById("cash");
const purchaseBtn = document.getElementById("purchase-btn");
const totalPriceElement = document.getElementById("price-total");
const cashInDrawerDiv = document.getElementById("cash-in-drawer");
const cashInDrawerSpans = document.querySelectorAll("#cash-in-drawer span");

const changeDueArr = [
  ['PENNY', 0],
  ['NICKEL', 0],
  ['DIME', 0],
  ['QUARTER', 0],
  ['ONE', 0],
  ['FIVE', 0],
  ['TEN', 0],
  ['TWENTY', 0],
  ['ONE HUNDRED', 0]
];

totalPriceElement.textContent = `Total: $${price}`;

cashInDrawerSpans.forEach((span, index) => span.innerText += cid[index][1]);

const arrSum = (arr) => {
  let sum = 0;
  for (let i = 0; i < arr.length; i++){
    let num = arr[i][1];
    sum += num;
  }
  return sum.toFixed(2);
}


const calculateChange = () => {
  let number = parseFloat(cash.value);
  if (number < price) {
    alert("Customer does not have enough money to purchase the item");
  } else if (number === price) {
    changeDueElement.textContent = "No change due - customer paid with exact cash";
  } else {
    const changeDue = number - price;
    return changeDue.toFixed(2);
  }
}

const updateCID = (cid, changeDueArr) => {
  for (let i = 0; i < cid.length; i++) {
      cid[i][1] -= changeDueArr[i][1];
      cashInDrawerSpans[i].innerText = cid[i][1].toFixed(2);
  }
}


const findDenominations = (num) => {
  for (let i = currencyUnits.length - 1; i >= 0; i--) {
    let currentDenominationValue = currencyUnits[i][1];

    let quotient = Math.floor(num / currentDenominationValue);     

    let denominationFitsIn = currentDenominationValue * quotient;
    
    let currentDenominationValueInRegister = cid[i][1];

    if (denominationFitsIn <= currentDenominationValueInRegister) {
      num = (num - denominationFitsIn).toFixed(2);
      changeDueArr[i][1] = denominationFitsIn;
    } else {
      num = (num - currentDenominationValueInRegister).toFixed(2);
      changeDueArr[i][1] = currentDenominationValueInRegister;
    }     
    console.log(`${num}`);
  }
  console.log(changeDueArr);
  console.log(num);
  return Number(num);
}

const displayChangeDueArr = (changeDueArr) => {
  for (let i = changeDueArr.length - 1; i >= 0; i--) {
    let label = changeDueArr[i][0];
    let value = changeDueArr[i][1];
    if (value !== 0) {
changeDueElement.textContent += ` ${label}: $${value}`;
    }
  }
}

const purchase = () => {
  let totalChangeDue = calculateChange();
  console.log(totalChangeDue);
  let sumCID = arrSum(cid);
  console.log(sumCID);

  let leftover = findDenominations(totalChangeDue);

  if (totalChangeDue === sumCID && leftover === 0) {

    changeDueElement.textContent = "Status: CLOSED";
    displayChangeDueArr(changeDueArr);
    updateCID(cid, changeDueArr);
    console.log("This block ran 1");

  } else if (totalChangeDue < sumCID && leftover === 0) {
    
    changeDueElement.textContent = "Status: OPEN";
    displayChangeDueArr(changeDueArr);
    updateCID(cid, changeDueArr);
    console.log("This block ran 2");

  } else if (totalChangeDue > sumCID && leftover > 0) {
    
    changeDueElement.textContent = "Status: INSUFFICIENT_FUNDS";
    console.log("This block ran 3");
  }

}

purchaseBtn.addEventListener("click", purchase);

https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures-v8/build-a-cash-register-project/build-a-cash-register

2

Hey can you explain exactly what happens when it’s greater than 37?

3

On the preview nothing occurs, but i see that in my console, the findDenominations function works fine and creates a new array for the changeDue/all the correct denominations but nothing in the if/else statement in the purchase function runs

when i put in a value that is equal to the sum of cash in the drawer plus price of item, the if/else statement runs and the preview shows Status Closed so the problem is only input values from 35-to $336

4

I think the problem is somewhere in here, in my if/else wording as when i take this out and just call the display and update functions everything works fine

if (totalChangeDue == sumCID && leftover === 0) {
    changeDueElement.innerHTML = `<p>Status: CLOSED</p>`;
    displayChangeDueArr(changeDueArr);
    updateCID(cid, changeDueArr);
  } else if (totalChangeDue < sumCID && leftover === 0) {
    changeDueElement.innerHTML = `<p>Status: OPEN</p>`;
    displayChangeDueArr(changeDueArr);
    updateCID(cid, changeDueArr);
  } else if (totalChangeDue > sumCID || leftover > 0) {
    changeDueElement.innerHTML = `<p>Status: INSUFFICIENT_FUNDS</p>`;
  }