pub fn main () {
    println!("{}", main_test());
}

#[inline(never)]
fn main_test() -> i64 {
    let mut arr = [ 1, 2];
    fuse_test(&mut arr);
    arr[0]
}

fn fuse_test(arr: &mut [i64]) {
    arr.iter_mut()
        .map(|e| {
            *e = *e * 5;
            *e
        })
        .filter(|e| *e % 10 == 0)
        .count();
}