#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main() {
    int N;
    cin >> N;
    int S[N], T[N];
    int s1 = 0, s2 = 0, t1 = 0, t2 = 0;
    for (int i = 0; i < N; i++) {
        cin >> S[i];
        if (S[i] == 2) s2++;
    }
    for (int i = 0; i < N; i++) {
        cin >> T[i];
        if (T[i] == 2) t2++;
    }
    for (int i = 0; i < N; i++) {
        if (s2 == 0 && T[i] == 1) t1++;
        if (t2 == 0 && S[i] == 1) s1++;
    }
    //int k = N * s2 + N * t2 - s2 * t2;
    int ans = N * s2 + N * t2 - s2 * t2 + max(s1, t1);
    cout << ans << "\n";
}