#![allow(unused_imports)]
use std::cmp::*;
use std::collections::*;
use std::io::Write;
use std::ops::Bound::*;

#[allow(unused_macros)]
macro_rules! debug {
    ($($e:expr),*) => {
        #[cfg(debug_assertions)]
        $({
            let (e, mut err) = (stringify!($e), std::io::stderr());
            writeln!(err, "{} = {:?}", e, $e).unwrap()
        })*
    };
}

fn main() {
    let n = read::<usize>();
    let mut s = read_vec::<i64>();
    let mut t = read_vec::<i64>();

    if !s.iter().any(|&x| x == 2) && !t.iter().any(|&x| x == 2) {
        let ans = max(
            s.iter().filter(|&&x| x == 1).count(),
            t.iter().filter(|&&x| x == 1).count(),
        );
        println!("{}", ans);
        return;
    }
    if s.iter().any(|&x| x == 2) && t.iter().any(|&x| x == 2) {
        let mut ans = n * s.iter().filter(|&&x| x == 2).count();
        ans += (n - s.iter().filter(|&&x| x == 2).count()) * t.iter().filter(|&&x| x == 2).count();
        println!("{}", ans);
        return;
    }
    if t.iter().any(|&x| x == 2) {
        std::mem::swap(&mut s, &mut t);
    }

    let mut ans = 0;
    for i in 0..n {
        if s[i] == 2 {
            ans += n;
        } else if s[i] == 1 {
            ans += 1;
        }
    }
    println!("{}", ans);
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}