fn main() {
    let mut sum = 0;
    for n in 1..999 {
        if n % 3 == 0 || n % 5 == 0 {
            sum += n;
        }
    }
    println!("Sum of numbers % 3 or % 5 below 1000 is {}", sum);

    let mut sum_fib = 2;
    let mut last = 1;
    let mut curr = 1;

    while curr < 4000000 {
        let next = last + curr;
        if next % 2 == 0 {
            sum_fib += next;
        }
        last = curr;
        curr = next;
    }
     println!("Sum of even fib numbers below 4,000,000 is {}", sum_fib);
}