Euler Project #6: Difference of Square of Sums and Sum of Squares

The sum of the squares of the first ten natural numbers is, 1² + 2² + … + 10² = 385

The square of the sum of the first ten natural numbers is, (1 + 2 + … + 10)² = 55² = 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.

// sumOfSquares: 338350
// squareOfSums: 25502500
// diff: 25164150
var sumOfSquares = 0
var squareOfSums = 0
for x in 1...100
{
sumOfSquares += x*x
squareOfSums += x
}
sumOfSquares
squareOfSums *= squareOfSums
let diff = squareOfSums - sumOfSquares