Program to find largest of three numbers - JavaScript

We are required to write a JavaScript function that takes in three or more numbers and returns the largest of those numbers.

For example: If the input numbers are ?

4, 6, 7, 2, 3

Then the output should be ?

7

Method 1: Using Math.max() with Spread Operator

The simplest approach is using the built-in Math.max() function with the spread operator:

const findLargest = (...nums) => {
    return Math.max(...nums);
};

console.log(findLargest(4, 6, 7, 2, 3));
console.log(findLargest(15, 8, 23, 1));

7
23

Method 2: Using Loop Iteration

For manual comparison, we can iterate through the numbers and track the maximum:

const findGreatest = (...nums) => {
    let max = -Infinity;
    for(let i = 0; i < nums.length; i++){
        if(nums[i] > max){
            max = nums[i];
        }
    }
    return max;
};

console.log(findGreatest(5, 6, 3, 5, 7, 5));
console.log(findGreatest(-10, -5, -20));

7
-5

Method 3: Using reduce() Method

We can also use the reduce() method for a functional programming approach:

const findLargestReduce = (...nums) => {
    return nums.reduce((max, current) => current > max ? current : max, -Infinity);
};

console.log(findLargestReduce(12, 45, 23, 67, 1));
console.log(findLargestReduce(3.5, 2.1, 9.8));

67
9.8

Handling Edge Cases

Here's how these methods handle special cases:

// Empty array
console.log(Math.max());  // -Infinity

// Single number
console.log(findLargest(42));

// Negative numbers
console.log(findLargest(-1, -5, -3));

-Infinity
42
-1

Comparison

Conclusion

Use Math.max() with spread operator for the most efficient and readable solution. The loop method provides better understanding of the underlying logic for learning purposes.