/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author champon
 */

//<editor-fold desc="definitions">
#include <bits/stdc++.h>
#define se cout << "test ok" << endl;
#define sp << " " <<
#define enl "\n"
using namespace std;
using ll=long long;
using ld=long double;
using vi = vector<int>;
using vii = vector<vector<int>>;
using viii = vector<vector<vector<int>>>;
using vl = vector<ll>;
using vll = vector<vector<ll>>;
using vlll = vector<vector<vector<ll>>>;
using vc = vector<char>;
using vcc = vector<vector<char>>;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
ll mod = ll(1e9)+7;
ll inf = ll(1e18);
void bl(bool b, ostream& out=cout){ out << (b ? "Yes" : "No") << endl; }
void bl2(bool b, ostream& out=cout){ out << (b ? "YES" : "NO") << endl; }
template<typename T> inline bool chmax(T &a, T b){ if(a<b){a=b; return true;} return false; }
template<typename T> inline bool chmin(T &a, T b){ if(a>b){a=b; return true;} return false; }
int dx[] = {1, 0, -1, 0, 1, -1, 1, -1};
int dy[] = {0, 1, 0, -1, 1, -1, -1, 1};

#ifndef INCLUDE_DEBUG_HPP
#define INCLUDE_DEBUG_HPP

#define TO_STRING(varName) # varName
#include <iostream>
#include <vector>
#include <map>
using namespace std;

namespace dbg {
    using ll = long long;

    class Debug {
        void prefix() { cout << "\033[7m\033[35m" << " DEBUG " << "\033[0m" << endl; }

        void out_helper(){ cout << endl; }

        void out_with_name_helper(){ cout << endl; }

        template<typename T1, typename... T2>
        void out_helper(T1 v, T2... args);

        template<typename T1, typename... T2>
        void out_with_name_helper(string s, T1 v, T2... args);

        // value
        template<typename T>
        void print(T val);

        // pair
        template<typename A, typename B>
        void print(pair<A, B> p);

        // tuple
        template<typename A, typename B, typename C>
        void print(tuple<A, B, C> t);

        // vector
        template<typename T>
        void print(vector<T> &vec);

        // set
        template<typename T>
        void print(set<T> &st);

        // map
        template<typename A, typename B>
        void print(map<A, B> mp);
    public:
        Debug(){}

        template<typename... T>
        void out(T... args){
            prefix();
            out_helper(args...);
        }

        template<typename... T>
        void out_with_name(T... args){
            prefix();
            out_with_name_helper(args...);
        }

        template<typename T>
        void outg(vector<vector<T>> &g) {
            prefix();
            for(auto& v1 : g){
                for(auto& v2 : v1) {
                    cout << v2 << " ";
                }
                cout << endl;
            }
        }
    };

    template<typename T1, typename... T2>
    void Debug::out_helper(T1 v, T2... args) {
        print(v); cout << endl;
        out_helper(args...);
    }

    template<typename T1, typename... T2>
    void Debug::out_with_name_helper(string s, T1 v, T2... args) {
        cout << s << ": "; print(v); cout << endl;
        out_with_name_helper(args...);
    }

    template<typename T>
    void Debug::print(T val){
        cout << val;
    }

    template<typename A, typename B>
    void Debug::print(pair<A, B> p){
        cout << "("; print(p.first); cout << ", "; print(p.second); cout << ")";
    }

    template<typename A, typename B, typename C>
    void Debug::print(tuple<A, B, C> t) {
        cout << "("; print(get<0>(t)); cout << ", "; print(get<1>(t)); cout << ", "; print(get<2>(t)); cout << ")";
    }

    template<typename T>
    void Debug::print(vector<T>& vec) {
        cout << "[";
        bool fir = true;
        for(auto& e : vec) {
            if(!fir) cout << " ";
            print(e), fir=false;
        }
        cout << "]";
    }

    template<typename T>
    void Debug::print(set<T> &st){
        cout << "{";
        bool fir = true;
        for(auto& e : st) {
            if(!fir) cout << " ";
            print(e), fir=false;
        }
        cout << "}";
    }

    template<typename A, typename B>
    void Debug::print(map<A, B> mp){
        cout << "{";
        bool fir = true;
        for(auto& p : mp){
            if(!fir) cout << " ";
            print(p), fir=false;
        }
        cout << "}";
    }

}

#endif //INCLUDE_DEBUG_HPP

dbg::Debug debug;
//</editor-fold>

#ifndef INCLUDE_MINT_HPP
#define INCLUDE_MINT_HPP

namespace mint {

    using ll = long long;

    class Mint {
    public:
        ll v;
        ll mod;

        Mint(ll v=0, ll mod=ll(1e9)+7) : mod(mod), v((v % mod + mod) % mod) {}

        friend ostream& operator<<(ostream& os, const Mint& val) {
            os << val.v;
            return os;
        }

        Mint operator-() const { return Mint(-v); }
        Mint operator+(const Mint rhs) const {
            Mint res(*this);
            return res += rhs;
        }
        Mint operator-(const Mint rhs) const {
            Mint res(*this);
            return res -= rhs;
        }
        Mint operator*(const Mint rhs) const {
            Mint res(*this);
            return res *= rhs;
        }
        Mint &operator+=(const Mint rhs) {
            if ((v += rhs.v) >= mod) v -= mod;
            return *this;
        }
        Mint &operator-=(const Mint rhs) {
            if ((v += mod - rhs.v) >= mod) v -= mod;
            return *this;
        }
        Mint &operator*=(const Mint rhs) {
            (v *= rhs.v) %= mod;
            return *this;
        }
        Mint pow(ll t) const {
            if (!t) return 1;
            Mint b = pow(t >> 1);
            b *= b;
            if (t & 1) b *= *this;
            return b;
        }
        Mint inv() const {
            return pow(mod - 2);
        }
        Mint &operator/=(const Mint rhs) {
            return (*this) *= rhs.inv();
        }
        Mint operator/(const Mint rhs) const {
            Mint res(*this);
            return res /= rhs;
        }
    };

}

#endif //INCLUDE_MINT_HPP

using mint::Mint;

class D {
public:
	void solve(std::istream& in, std::ostream& out){
	    ll n, m;
	    in >> n >> m;
	    vl x(n), y(m);
	    for(int i=0; i<n; i++) in >> x[i];
	    for(int i=0; i<m; i++) in >> y[i];

	    sort(x.begin(), x.end());
	    sort(y.begin(), y.end());

	    vector<Mint> xv(n);
	    for(int i=1; i<n; i++){
	        xv[i] = Mint(x[i] - x[i-1]) * Mint(y[1] - y[0]);
	        xv[i] *= (i*(n-i));
	    }
	    for(ll i=1; i<n; i++) xv[i] += xv[i-1];

	    vector<Mint> yv(m);
	    yv[1] = xv[n-1];
	    for(int i=2; i<m; i++){
	        yv[i] = yv[i-1] / (y[i-1] - y[i-2]) * (y[i] - y[i-1]);
	    }
	    for(ll i=1; i<m; i++) yv[i] *= (i * (m-i));
	    for(int i=1; i<m; i++) yv[i] += yv[i-1];

	    //debug.out(xv, yv);

	    out << yv[m-1] << endl;
	}
};


int main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
	D solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	solver.solve(in, out);
	return 0;
}


Measured memory_bytes: 4992