Problem:
Score : 500 points

Problem Statement

On a two-dimensional plane, there are m lines drawn parallel to the x axis, and n lines drawn parallel to the y axis.
Among the lines parallel to the x axis, the i-th from the bottom is represented by y = y_i.
Similarly, among the lines parallel to the y axis, the i-th from the left is represented by x = x_i.

For every rectangle that is formed by these lines, find its area, and print the total area modulo 10^9+7.

That is, for every quadruple (i,j,k,l) satisfying 1\leq i < j\leq n and 1\leq k < l\leq m, find the area of the rectangle formed by the lines x=x_i, x=x_j, y=y_k and y=y_l, and print the sum of these areas modulo 10^9+7.

Constraints

2 \leq n,m \leq 10^5

-10^9 \leq x_1 < ... < x_n \leq 10^9

-10^9 \leq y_1 < ... < y_m \leq 10^9

x_i and y_i are integers.

Input

Input is given from Standard Input in the following format:

n m
x_1 x_2 ... x_n
y_1 y_2 ... y_m

Output

Print the total area of the rectangles, modulo 10^9+7.

Sample Input 1

3 3
1 3 4
1 3 6

Sample Output 1

60

The following figure illustrates this input:

The total area of the nine rectangles A, B, ..., I shown in the following figure, is 60.

Sample Input 2

6 5
-790013317 -192321079 95834122 418379342 586260100 802780784
-253230108 193944314 363756450 712662868 735867677

Sample Output 2

835067060

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.math.BigInteger;
import java.util.Scanner;
public class Main {
	public static void main(String[] args){
		Main main = new Main();
		main.solveD();
	}

	private void solveA() {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		if (a - b == b - c) {
			System.out.println("YES");
		} else {
			System.out.println("NO");
		}
	}

	private void solveB() {
		Scanner sc = new Scanner(System.in);
		String o = sc.nextLine();
		String e = sc.nextLine();
		StringBuilder sb = new StringBuilder();
		for (int i = 0; i < e.length(); i++) {
			sb.append(o.charAt(i));
			sb.append(e.charAt(i));
		}
		if (o.length() != e.length()) {
			sb.append(o.charAt(o.length() - 1));
		}
		System.out.println(sb.toString());
	}

	private void solveC() {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		sc.nextLine();
		int[] min = new int[26];
		for (int i = 0; i < 26; i++) {
			min[i] = 51;
		}
		for (int i = 0; i < n; i++) {
			int[] tmp = new int[26];
			String buffer = sc.nextLine();
			for (int j = 0; j < buffer.length(); j++) {
				char asc = buffer.charAt(j);
				tmp[(asc - 'a')]++;
			}
			for (int j = 0; j < 26; j++) {
				if (min[j] > tmp[j]) {
					min[j] = tmp[j];
				}
			}
		}
		StringBuilder sb = new StringBuilder();
		for (char c = 'a'; c <= 'z'; c++) {
			for (int i = 0; i < min[c - 'a']; i++) {
				sb.append(c);
			}
		}
		System.out.println(sb.toString());
	}

	private void solveD() {
		Scanner sc = new Scanner(System.in);
		BigInteger MOD = BigInteger.valueOf(1000000007);
		int n = sc.nextInt();
		int m = sc.nextInt();
		BigInteger prev = null;
		BigInteger sum_x = BigInteger.ZERO;
		for (int i = 0; i < n; i++) {
			BigInteger tmp = BigInteger.valueOf(sc.nextInt());
			if (prev != null) {
				sum_x = sum_x.add(tmp.subtract(prev).multiply(BigInteger.valueOf(i * (n - i))).remainder(MOD));
			}
			prev = tmp;
		}
		prev = null;
		BigInteger sum_y = BigInteger.ZERO;
		for (int i = 0; i < m; i++) {
			BigInteger tmp = BigInteger.valueOf(sc.nextInt());
			if (prev != null) {
				sum_y = sum_y.add(tmp.subtract(prev).multiply(BigInteger.valueOf(i * (m - i))).remainder(MOD));
			}
			prev = tmp;
		}
		sum_x = sum_x.remainder(MOD);
		sum_y = sum_y.remainder(MOD);
		BigInteger ans = sum_x.multiply(sum_y).remainder(MOD);
		System.out.println(ans);
	}
}