Question

Write a JS program that performs and outputs different operations on an array of elements. Implement the following operations:

• Sum(ai) - calculates the sum all elements from the input array
• Sum(1/ai) - calculates the sum of the inverse values (1/ai) of all elements from the array
• Concat(ai) - concatenates the string representations of all elements from the array

The input comes as an array of number elements

Examples:

Input:
[1, 2, 3]

Output:
6
1.8333
123

---

Input:
[2, 4, 8, 16]

Output:
30
0.9375
24816

The output should be printed on the console on a new line for each of the operations.

Answer 1

Here is my JS code:

function aggregateElements(input) {
    let elements = input.map(Number);
    aggregate(elements, 0, (a, b)=>a + b);
    aggregate(elements, 0, (a, b)=>a + 1 / b);
    aggregate(elements, "", (a, b)=>a + b);

    function aggregate(arr, initVal, func) {
        let val = initVal;
        for (let i = 0; i < arr.length; i++) {
            val = func(val, arr[i]);
        }
        console.log(val);
    }
}

aggregateElements([10, 20, 30]);