Binary Search Iterative Approach in DSA Typescript - Build from Scratch

Binary Search Iterative Approach

📖 Scenario: You have a sorted list of numbers representing book IDs in a library. You want to quickly find if a specific book ID exists in the list.

🎯 Goal: Build a program that uses the iterative binary search method to find a given book ID in the sorted list.

📋 What You'll Learn

Create a sorted array of book IDs

Set a target book ID to search for

Implement the iterative binary search function

Print the index of the target book ID if found, or -1 if not found

💡 Why This Matters

🌍 Real World

Binary search is used in many applications like searching in databases, finding words in dictionaries, or looking up records quickly.

💼 Career

Understanding binary search helps in software development roles where efficient searching and sorting are important, such as backend development, data engineering, and algorithm design.

1

Create the sorted array of book IDs

Create a variable called bookIDs and assign it the sorted array [101, 203, 305, 407, 509, 611, 713].

DSA Typescript

# Your code here

Hint

Use const to create the array and assign the exact numbers in sorted order.

2

Set the target book ID to search

Create a variable called target and set it to the number 407.

DSA Typescript

const bookIDs = [101, 203, 305, 407, 509, 611, 713];
# Your code here

Hint

Use const to create the target variable with the exact value 407.

3

Implement the iterative binary search function

Write a function called binarySearch that takes parameters arr (array of numbers) and target (number). Use a while loop with variables left and right to find the target in arr iteratively. Return the index if found, otherwise return -1.

DSA Typescript

const bookIDs = [101, 203, 305, 407, 509, 611, 713];
const target = 407;

# Your code here

Hint

Use left and right to track the search range. Calculate mid inside the loop. Compare arr[mid] with target and adjust left or right accordingly.

4

Print the search result

Call the binarySearch function with bookIDs and target, and print the returned index using console.log.

DSA Typescript

const bookIDs = [101, 203, 305, 407, 509, 611, 713];
const target = 407;

function binarySearch(arr: number[], target: number): number {
    let left = 0;
    let right = arr.length - 1;
    while (left <= right) {
        const mid = Math.floor((left + right) / 2);
        if (arr[mid] === target) {
            return mid;
        } else if (arr[mid] < target) {
            left = mid + 1;
        } else {
            right = mid - 1;
        }
    }
    return -1;
}

# Your code here

Hint

Use console.log(binarySearch(bookIDs, target)) to print the index.