project euler problem 6

main.rs

fn main() {
    let upper = 100;
    let sum_of_squares = (0..upper).fold(0, |acc, i| acc + (i * i));
    let sum = (0..upper).fold(0, |acc, i| acc + i);
    let square_of_sum = sum * sum;
    let difference = square_of_sum - sum_of_squares;
    println!("{:?}", difference);
}