#include <bits/stdc++.h>
#define ent '\n'
#define f first
#define s second

using namespace std;

template <typename T>
T inverse(T a, T m) {
    T u = 0, v = 1;
    while (a != 0) {
        T t = m / a;
        m -= t * a; swap(a, m);
        u -= t * v; swap(u, v);
    }
    assert(m == 1);
    return u;
}

template <typename T>
class Modular {
public:
    using Type = typename decay<decltype(T::value)>::type;

    constexpr Modular() : value() {}
    template <typename U>
    Modular(const U& x) {
        value = normalize(x);
    }

    template <typename U>
    static Type normalize(const U& x) {
        Type v;
        if (-mod() <= x && x < mod()) v = static_cast<Type>(x);
        else v = static_cast<Type>(x % mod());
        if (v < 0) v += mod();
        return v;
    }

    const Type& operator()() const { return value; }
    template <typename U>
    explicit operator U() const { return static_cast<U>(value); }
    constexpr static Type mod() { return T::value; }

    Modular& operator+=(const Modular& other) { if ((value += other.value) >= mod()) value -= mod(); return *this; }
    Modular& operator-=(const Modular& other) { if ((value -= other.value) < 0) value += mod(); return *this; }
    template <typename U> Modular& operator+=(const U& other) { return *this += Modular(other); }
    template <typename U> Modular& operator-=(const U& other) { return *this -= Modular(other); }
    Modular& operator++() { return *this += 1; }
    Modular& operator--() { return *this -= 1; }
    Modular operator++(int) { Modular result(*this); *this += 1; return result; }
    Modular operator--(int) { Modular result(*this); *this -= 1; return result; }
    Modular operator-() const { return Modular(-value); }

    template <typename U = T>
    typename enable_if<is_same<typename Modular<U>::Type, int>::value, Modular>::type& operator*=(const Modular& rhs) {
        value = normalize(static_cast<int64_t>(value) * static_cast<int64_t>(rhs.value));
        return *this;
    }
    template <typename U = T>
    typename enable_if<is_same<typename Modular<U>::Type, long long>::value, Modular>::type& operator*=(const Modular& rhs) {
        long long q = static_cast<long long>(static_cast<long double>(value) * rhs.value / mod());
        value = normalize(value * rhs.value - q * mod());
        return *this;
    }
    template <typename U = T>
    typename enable_if<!is_integral<typename Modular<U>::Type>::value, Modular>::type& operator*=(const Modular& rhs) {
        value = normalize(value * rhs.value);
        return *this;
    }

    Modular& operator/=(const Modular& other) { return *this *= Modular(inverse(other.value, mod())); }

    friend const Type& abs(const Modular& x) { return x.value; }

    template <typename U>
    friend bool operator==(const Modular<U>& lhs, const Modular<U>& rhs);

    template <typename U>
    friend bool operator<(const Modular<U>& lhs, const Modular<U>& rhs);

    template <typename V, typename U>
    friend V& operator>>(V& stream, Modular<U>& number);

private:
    Type value;
};

template <typename T> bool operator==(const Modular<T>& lhs, const Modular<T>& rhs) { return lhs.value == rhs.value; }
template <typename T, typename U> bool operator==(const Modular<T>& lhs, U rhs) { return lhs == Modular<T>(rhs); }
template <typename T, typename U> bool operator==(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) == rhs; }

template <typename T> bool operator!=(const Modular<T>& lhs, const Modular<T>& rhs) { return !(lhs == rhs); }
template <typename T, typename U> bool operator!=(const Modular<T>& lhs, U rhs) { return !(lhs == rhs); }
template <typename T, typename U> bool operator!=(U lhs, const Modular<T>& rhs) { return !(lhs == rhs); }

template <typename T> bool operator<(const Modular<T>& lhs, const Modular<T>& rhs) { return lhs.value < rhs.value; }

template <typename T> Modular<T> operator+(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) += rhs; }
template <typename T, typename U> Modular<T> operator+(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) += rhs; }
template <typename T, typename U> Modular<T> operator+(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) += rhs; }

template <typename T> Modular<T> operator-(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) -= rhs; }
template <typename T, typename U> Modular<T> operator-(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) -= rhs; }
template <typename T, typename U> Modular<T> operator-(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) -= rhs; }

template <typename T> Modular<T> operator*(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) *= rhs; }
template <typename T, typename U> Modular<T> operator*(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) *= rhs; }
template <typename T, typename U> Modular<T> operator*(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) *= rhs; }

template <typename T> Modular<T> operator/(const Modular<T>& lhs, const Modular<T>& rhs) { return Modular<T>(lhs) /= rhs; }
template <typename T, typename U> Modular<T> operator/(const Modular<T>& lhs, U rhs) { return Modular<T>(lhs) /= rhs; }
template <typename T, typename U> Modular<T> operator/(U lhs, const Modular<T>& rhs) { return Modular<T>(lhs) /= rhs; }

template<typename T, typename U>
Modular<T> power(const Modular<T>& a, const U& b) {
    assert(b >= 0);
    Modular<T> x = a, res = 1;
    U p = b;
    while (p > 0) {
        if (p & 1) res *= x;
        x *= x;
        p >>= 1;
    }
    return res;
}

template <typename T>
bool IsZero(const Modular<T>& number) {
    return number() == 0;
}

template <typename T>
string to_string(const Modular<T>& number) {
    return to_string(number());
}

// U == std::ostream? but done this way because of fastoutput
template <typename U, typename T>
U& operator<<(U& stream, const Modular<T>& number) {
    return stream << number();
}

// U == std::istream? but done this way because of fastinput
template <typename U, typename T>
U& operator>>(U& stream, Modular<T>& number) {
    typename common_type<typename Modular<T>::Type, long long>::type x;
    stream >> x;
    number.value = Modular<T>::normalize(x);
    return stream;
}

// using ModType = int;

// struct VarMod { static ModType value; };
// ModType VarMod::value;
// ModType& md = VarMod::value;
// using Mint = Modular<VarMod>;

const int md = (int)1e9 + 7;
using Mint = Modular<std::integral_constant<decay<decltype(md)>::type, md>>;
#define int long long

typedef long long ll;
const int maxn = 5e5 + 12;
const int mod = 1e9 + 7;

Mint sums[maxn][4];
Mint dps[maxn][4];
Mint sum[maxn][4];
Mint dp[maxn][4];
int a[maxn];
int b[maxn];
int n, m, s;

void solve(){
    cin >> n;
    for(int i=1;i<=n;i++){
        cin >> a[i];
    }
    for(int i=1;i<=n;i++) {
        cin >> b[i];
    }
    dp[0][0] = 1;
    sum[0][0] = 0;
    for(int i=1;i<=n;i++){
        for(int x=0;x<=2;x++){
            if(a[i] >= x){
                dp[i][a[i]] += dp[i-1][x];
                sum[i][a[i]] += sum[i-1][x];
            }
            else{
                dp[i][x] += dp[i-1][x];
                sum[i][x] += sum[i-1][x] + dp[i-1][x] * (x - a[i]);
            }
            if(b[i] >= x){
                dp[i][b[i]] += dp[i-1][x];
                sum[i][b[i]] += sum[i-1][x];
            }
            else{
                dp[i][x] += dp[i-1][x];
                sum[i][x] += sum[i-1][x] + dp[i-1][x] * (x - b[i]);
            }
        }
    }
    dps[n+1][0] = 1;
    for(int i=n;i;i--){
        for(int x=0;x<=2;x++){
            if(a[i] >= x){
                dps[i][a[i]] += dps[i+1][x];
                sums[i][a[i]] += sums[i+1][x];
            }
            else{
                dps[i][x] += dps[i+1][x];
                sums[i][x] += sums[i+1][x] + dps[i+1][x] * (x - a[i]);
            }
            if(b[i] >= x){
                dps[i][b[i]] += dps[i+1][x];
                sums[i][b[i]] += sums[i+1][x];
            }
            else{
                dps[i][x] += dps[i+1][x];
                sums[i][x] += sums[i+1][x] + dps[i+1][x] * (x - b[i]);
            }
        }
    }
    Mint ans = 0;
    for(int i=1;i<=n;i++){
        Mint cntl = 0, sl = 0, cntr = 0, sr = 0;
        for(int x=0;x<=a[i];x++){
            cntr += dps[i+1][x];
            sr += sums[i+1][x];
            if(x == a[i]) break;
            cntl += dp[i-1][x];
            sl += sum[i-1][x];
        }
        ans += sr * cntl + sl * cntr;
    }
    for(int i=1;i<=n;i++){
        Mint cntl = 0, sl = 0, cntr = 0, sr = 0;
        for(int x=0;x<=b[i];x++){
            cntr += dps[i+1][x];
            sr += sums[i+1][x];
            if(x == b[i]) break;
            cntl += dp[i-1][x];
            sl += sum[i-1][x];
        }
        ans += sr * cntl + sl * cntr;
    }
    cout << ans << ent;
}

signed main(){
    srand(time(0));
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t = 1;
    // cin >> t;
    while(t--){
        solve();
    }
}