fn has_even<T0, RT>(numbers: T0) -> RT {
    for num in numbers {
        if num % 2 == 0 {
            return true;
        }
    }
    return false;
}
fn main() {
    let vec = vec![1, 9, 2, 5];
    let even_exists = has_even(vec);
    println!("{:?} {:?} ", "Has even number", even_exists);
}