#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("YES");}else{puts("NO");}
#define MAX_N 200005

int main() {
    int n; cin >> n;
    int a[n] = {};
    int ma = 0;
    rep(i,n){
        cin >> a[i];
        ma = max(ma,a[i]);
    }
    int mb = 0;
    int b[n] = {};
    rep(i,n){
        cin >> b[i];
        mb = max(mb,b[i]);
    }
    int ans = 0;
    if(ma == 2 || mb == 2){
        int cnt1 = 0, cnt2 = 0;
        rep(i,n){
            if(a[i] == 2) cnt1++;
            if(b[i] == 2) cnt2++;
        }
        ans = n * cnt1 + n * cnt2 - cnt1 * cnt2;
        if(cnt2==0){
            rep(i,n) if(a[i]==1) ans++;
        }else if(cnt1 == 0){
            rep(i,n) if(b[i]==1) ans++;
        }
    }else{
        int cnt1 = 0, cnt2 = 0;
        rep(i,n){
            if(a[i] == 1) cnt1++;
            if(b[i] == 1) cnt2++;
        }
        ans = max(cnt1,cnt2);
    }

    cout << ans << endl;
    return 0;
}