Heap Concept Structure and Properties in DSA Javascript - Build from Scratch

Heap Concept Structure and Properties

📖 Scenario: Imagine you are organizing a priority queue for tasks in a to-do app. Each task has a priority number. You want to store these tasks so that the highest priority task is always easy to find.

🎯 Goal: You will create a simple heap structure using an array to understand how tasks are stored and how the heap properties keep the highest priority task at the top.

📋 What You'll Learn

Create an array called tasks with specific priority numbers

Create a variable called heapSize to store the number of tasks

Write a function called isHeapPropertyValid to check if the array follows max-heap property

Print the result of the heap property check

💡 Why This Matters

🌍 Real World

Heaps are used in task scheduling, priority queues, and efficient sorting algorithms like heap sort.

💼 Career

Understanding heap structure helps in roles involving algorithm optimization, system design, and software development.

1

Create the tasks array

Create an array called tasks with these exact priority numbers in order: 40, 30, 20, 15, 10, 12, 8.

DSA Javascript

// Create the tasks array with given priorities
// Your code here

Hint

Use square brackets [] to create an array and separate numbers with commas.

2

Set the heap size

Create a variable called heapSize and set it to the length of the tasks array.

DSA Javascript

const tasks = [40, 30, 20, 15, 10, 12, 8];
// Create heapSize variable to store number of tasks
// Your code here

Hint

Use array.length to get the number of items in an array.

3

Check the max-heap property

Write a function called isHeapPropertyValid that takes the tasks array and heapSize as parameters. It should return true if every parent node is greater than or equal to its children (max-heap property), otherwise false. Use a for loop with variable i from 0 to Math.floor(heapSize / 2) - 1 to check each parent node.

DSA Javascript

const tasks = [40, 30, 20, 15, 10, 12, 8];
const heapSize = tasks.length;

// Write isHeapPropertyValid function below
// Your code here

Hint

Remember, for each parent at index i, left child is at 2*i + 1 and right child is at 2*i + 2.

4

Print the heap property check result

Use console.log to print the result of calling isHeapPropertyValid(tasks, heapSize).

DSA Javascript

const tasks = [40, 30, 20, 15, 10, 12, 8];
const heapSize = tasks.length;

function isHeapPropertyValid(tasks, heapSize) {
    for (let i = 0; i <= Math.floor(heapSize / 2) - 1; i++) {
        let left = 2 * i + 1;
        let right = 2 * i + 2;
        if (left < heapSize && tasks[i] < tasks[left]) {
            return false;
        }
        if (right < heapSize && tasks[i] < tasks[right]) {
            return false;
        }
    }
    return true;
}

// Print the result below
// Your code here

Hint

Use console.log to print the boolean result.