Build a Sorting Visualizer - Build a Sorting Visualizer

JavaScript
1

Tell us what’s happening:

My code can’t pass test 18 and I don’t know why. Any help is much appreciated.
After you click #sort-btn, #array-container should contain as many div elements as the steps required by the Bubble Sort algorithm to sort the starting array, including the div representing the starting array and a div representing the sorted array.

Your code so far

<!-- file: index.html -->
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Sorting Visualizer</title>
    <link rel="stylesheet" href="styles.css">
</head>

<body>
    <main>
        <div id="array-container">
            <div id="starting-array"></div>
        </div>
        <div id="btn-container">
            <button id="generate-btn" type="button">Generate Array</button>
            <button id="sort-btn" type="button">Sort Array</button>
        </div>
    </main>
    <script src="script.js"></script>
</body>

</html>

/* file: script.js */
let currentArray = [];

function generateElement() {
  return Math.floor(Math.random() * 100) + 1;
}

function generateArray() {
  const arr = [];
  for (let i = 0; i < 5; i++) {
    arr.push(generateElement());
  }
  return arr;
}

function generateContainer() {
  return document.createElement("div");
}

function fillArrContainer(container, arr) {
  container.innerHTML = ""; // Clear existing content
  arr.forEach(num => {
    const span = document.createElement("span");
    span.textContent = num;
    container.appendChild(span);
  });
}

function isOrdered(a, b) {
  return a <= b;
}

function swapElements(arr, index) {
  if (!isOrdered(arr[index], arr[index + 1])) {
    const temp = arr[index];
    arr[index] = arr[index + 1];
    arr[index + 1] = temp;
  }
}

function highlightCurrentEls(container, index) {
  const children = container.children;
  if (index < children.length) {
    children[index].style.border = "2px dashed red";
  }
  if (index + 1 < children.length) {
    children[index + 1].style.border = "2px dashed red";
  }
}

document.getElementById("generate-btn").addEventListener("click", function () {
  const arrayContainer = document.getElementById("array-container");
  arrayContainer.innerHTML = "";

  const startingArrayDiv = document.createElement("div");
  startingArrayDiv.id = "starting-array";
  arrayContainer.appendChild(startingArrayDiv);

  currentArray = generateArray();
  fillArrContainer(startingArrayDiv, currentArray);
});

document.getElementById("sort-btn").addEventListener("click", function () {
  if (currentArray.length === 0) return;
  const arrayContainer = document.getElementById("array-container");

  const startingArrayDiv = document.getElementById("starting-array");
  fillArrContainer(startingArrayDiv, currentArray);
  highlightCurrentEls(startingArrayDiv, 0);
  
  let arr = currentArray.slice();
  const n = arr.length;
  let comparisonCount = 0; // total comparisons performed

  for (let i = 0; i < n - 1; i++) {
    for (let j = 0; j < n - i - 1; j++) {
      comparisonCount++;
      if (comparisonCount === 1) {
        if (!isOrdered(arr[j], arr[j + 1])) {
          swapElements(arr, j);
        }
      } else {
        const stepContainer = generateContainer();
        fillArrContainer(stepContainer, arr);
        highlightCurrentEls(stepContainer, j);
        arrayContainer.appendChild(stepContainer);

        if (!isOrdered(arr[j], arr[j + 1])) {
          swapElements(arr, j);
        }
      }
    }
  }

  const finalContainer = generateContainer();
  fillArrContainer(finalContainer, arr);
  arrayContainer.appendChild(finalContainer);
});

/* file: styles.css */
* {
    box-sizing: border-box;
}

main {
    height: 100vh;
    display: flex;
    justify-content: center;
    flex-direction: column;
    align-items: center;
}

#array-container {
    max-height: 95vh;
    display: flex;
    flex-direction: column;
    flex-wrap: wrap;
    gap: 2px;

}

#array-container>div {
    min-width: 8rem;
    height: 2rem;
    box-shadow: rgba(50, 50, 93, 0.25) 0px 2px 5px -1px, rgba(0, 0, 0, 0.3) 0px 1px 3px -1px;
    border-radius: 10px;
    margin-bottom: 0.2rem;
    border: 2px solid darkgray;
    display: flex;
    justify-content: space-evenly;
    align-items: center;
}

#starting-array {
    border: 4px solid darkblue !important;
}

#btn-container {
    display: flex;
    justify-content: space-around;
}

button {
    padding: 2px;
    margin: 5px;
}

span {
    border-radius: 2px;
    padding: 0.5px;
    margin: 0
}

@media (min-width: 430px) {
  #array-container>div {
    min-width: 12rem;    
  }
  span {
    padding: 1px;
    margin: 1px;
  }
}

Your browser information:

User Agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36

Challenge Information:

Build a Sorting Visualizer - Build a Sorting Visualizer

2

Can you explain a bit about the algorithm that you’re using for Bubble Sort? How does it work?

Screenshot 2025-03-16 222446
Screenshot 2025-03-16 222446193×458 34.3 KB

It’s described like this in the instructions

When the last element of the sequence is reached, it starts a new cycle from the beginning of the sequence, and repeats the process until the elements are sorted. The algorithm stops after one cycle completes with no swaps.