Returning a range or a number that specifies the square root of a number in JavaScript

We need to write a JavaScript function that takes an integer n and returns either the exact square root (if n is a perfect square) or a range indicating where the square root falls between two consecutive integers.

Problem Requirements

• Return integer k if n is a perfect square, such that k * k == n
• Return a range (k, k+1) if n is not a perfect square, where k * k

Solution Approach

We use Math.sqrt() to calculate the square root, then check if it's a whole number using Math.floor(). If the square root is exact, we return it; otherwise, we return the floor and ceiling values as a range.

Example Implementation

const num = 83;
const squareRootRange = (num = 1) => {
    const exact = Math.sqrt(num);
    if(exact === Math.floor(exact)){
        return exact;
    } else { 
        return [Math.floor(exact), Math.ceil(exact)];
    }
};
console.log(squareRootRange(num));

[9, 10]

Testing with Perfect Squares

Let's test the function with perfect squares to see when it returns a single integer:

console.log(squareRootRange(16));  // Perfect square
console.log(squareRootRange(25));  // Perfect square
console.log(squareRootRange(30));  // Not a perfect square
console.log(squareRootRange(49));  // Perfect square

4
5
[5, 6]
7

How It Works

The function calculates Math.sqrt(num) and stores it in exact. If this value equals Math.floor(exact), it means the square root is a whole number (perfect square). Otherwise, we return an array containing the floor and ceiling of the square root, representing the range where the actual square root lies.

Conclusion

This solution efficiently determines whether a number is a perfect square and returns either the exact square root or the bounding range. The approach leverages JavaScript's built-in Math functions for accurate calculations.