Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wants to calculate the sum of all nice integers. Positive integer x is called nice if <image> and <image>, where k is some integer number in range [1, a].

By <image> we denote the quotient of integer division of x and y. By <image> we denote the remainder of integer division of x and y. You can read more about these operations here: http://goo.gl/AcsXhT.

The answer may be large, so please print its remainder modulo 1 000 000 007 (109 + 7). Can you compute it faster than Dreamoon?

Input

The single line of the input contains two integers a, b (1 ≤ a, b ≤ 107).

Output

Print a single integer representing the answer modulo 1 000 000 007 (109 + 7).

Examples

Input

1 1


Output

0


Input

2 2


Output

8

Note

For the first sample, there are no nice integers because <image> is always zero.

For the second sample, the set of nice integers is {3, 5}.
import java.util.*;
import java.io.*;
import java.lang.*;
import java.math.BigInteger;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */

public class sum {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        Task solver = new Task();
        solver.solve(1, in, out);
        out.close();
    }
}

class Task {
    static final int MOD = (int) (1e9 + 7);
    
    public BigInteger getSumFirstNumber(long n) {
        BigInteger temp = BigInteger.valueOf(n);
        temp = temp.multiply(BigInteger.valueOf(n + 1));
        temp = temp.divide(BigInteger.valueOf(2));
        return temp;
    }

    public void solve(int testNumber, InputReader in, PrintWriter out) {
        // type the code here
        long a = in.nextLong();
        long b = in.nextLong();
        BigInteger ans = getSumFirstNumber(a);
        ans = ans.multiply(BigInteger.valueOf(b));
        ans = ans.add(BigInteger.valueOf(a));

        BigInteger x = getSumFirstNumber(b - 1);
        ans = ans.multiply(x);
        out.println(ans.mod(BigInteger.valueOf(MOD)));
    }
}

class InputReader {
    public BufferedReader reader;
    public StringTokenizer tokenizer;

    public InputReader(InputStream stream) {
        reader = new BufferedReader(new InputStreamReader(stream), 32768);
        tokenizer = null;
    }

    public String next() {
        while (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }

    public long nextLong() {
        return Long.parseLong(next());
    }
    
    public double nextDouble() {
        return Double.parseDouble(next());
    }
}