Find the average of all elements of array except the largest and smallest - JavaScript

We are required to write a JavaScript function that takes in an array of numbers and returns the average of its elements excluding the smallest and largest numbers.

Approach

The solution involves finding the minimum and maximum values, calculating the total sum, then computing the average of remaining elements after excluding min and max values.

Example

const arr = [1, 4, 5, 3, 5, 6, 12, 5, 65, 3, 2, 65, 9];

const findExcludedAverage = arr => {
    const creds = arr.reduce((acc, val) => {
        let { min, max, sum } = acc;
        sum += val;
        if(val > max){
            max = val;
        }
        if(val 

Array: [1, 4, 5, 3, 5, 6, 12, 5, 65, 3, 2, 65, 9]
Average (excluding min/max): 5.636363636363637


How It Works

The function uses reduce() to traverse the array once, simultaneously tracking:

• min: Smallest value (starts with Infinity)
• max: Largest value (starts with -Infinity)
• sum: Total of all elements

Finally, it calculates: (sum - min - max) / (arr.length - 2)

Alternative Approach

const findExcludedAverageSimple = arr => {
    const min = Math.min(...arr);
    const max = Math.max(...arr);
    const sum = arr.reduce((total, num) => total + num, 0);
    
    return (sum - min - max) / (arr.length - 2);
};

const testArray = [10, 20, 30, 40, 50];
console.log("Simple approach result:", findExcludedAverageSimple(testArray));
console.log("Expected: (20+30+40)/3 =", (20+30+40)/3);

Simple approach result: 30
Expected: (20+30+40)/3 = 30

Conclusion

Both approaches work effectively. The reduce method is more efficient with a single pass, while the Math.min/max approach is more readable. Choose based on your preference for performance vs. code clarity.