6-Sum_square_difference.js

/*
The sum of the squares of the first ten natural numbers is,

1^2 + 2^2 + 3^2 + ... + 10^2 = 385

The square of the sum of the first ten natural numbers is,

( 1 + 2 + 3 + ... + 10 ) ^ 2 = 3025

Hence the difference between the sum of the squares of the first ten natural numbers and the square of the sum is .

3025 - 385 = 2640

Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum.

*/

let sumOfSquare = 0;
for (let i = 1; i <= 100; i++) {
    sumOfSquare += i * i;
}

let squareOfSum = ((100+1)*100/2) ** 2;
let diff = squareOfSum - sumOfSquare;

console.log(diff) // expect 25164150