Nth power rules them all!

7 kyu
Nth power rules them all!

You are provided with an array of positive integers and an additional integer n (n > 1).

Calculate the sum of each value in the array to the nth power. Then subtract the sum of the original array.

Examples
{1, 2, 3}, 3  -->  (1^3 + 2^3 + 3^3 ) - (1 + 2 + 3)  -->  36 - 6  -->  30
{1, 2}, 5     -->  (1^5 + 2^5) - (1 + 2) 


 
const modifiedSum = (a, n) => {
    return a.reduce((acc, curr) =>  acc + Math.pow(curr, n) - curr, 0)
}


console.log(modifiedSum([1, 2, 3], 3), 30); 
console.log(modifiedSum([1, 2], 5), 30);