Finding difference of greatest and the smallest digit in a number - JavaScript

We are required to write a JavaScript function that takes in a number and returns the difference between the greatest and the smallest digit present in it.

For example: If the number is 5464676, then the smallest digit here is 4 and the greatest is 7

Hence, our output should be 3

Example

Let's write the code for this function ?

const num = 44353456;
const difference = (num, min = Infinity, max = -Infinity) => {
    if(num){
        const digit = num % 10;
        return difference(Math.floor(num / 10), Math.min(digit, min),
        Math.max(digit, max));
    };
    return max - min;
};
console.log(difference(num));

3

Alternative Approach Using String Conversion

Here's another method that converts the number to a string and uses array methods:

const findDigitDifference = (num) => {
    const digits = num.toString().split('').map(Number);
    const max = Math.max(...digits);
    const min = Math.min(...digits);
    return max - min;
};

console.log(findDigitDifference(5464676));
console.log(findDigitDifference(12345));
console.log(findDigitDifference(99999));

3
4
0

How It Works

The recursive approach extracts digits one by one using modulo (%) and integer division. It tracks the minimum and maximum digits encountered, then returns their difference.

The string approach converts the number to a string, splits it into individual digits, and uses built-in Math.max() and Math.min() functions to find the extremes.

Conclusion

Both methods effectively find the difference between the largest and smallest digits in a number. The recursive approach is more memory-efficient, while the string method is more readable and easier to understand.