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.lang.String;
import java.lang.Math;
import java.io.*;
import java.util.Arrays;
import java.util.Scanner;
import javax.swing.JOptionPane;

public class Solution {
	
public static long mod = 1000000007;

	public static long BigMod(long B,long P,long M)
	{
		long R=1;
		while(P>0)
		{
			if(P%2==1)
			{
				R=(R*B)%M;}P/=2;B=(B*B)%M;
			}
			return R%M;
	}
	
	
	public static void main(String args[])throws IOException
	{
		long a,b,ans=0;
		a = nextLong();
		b = nextLong();	
		long R = ((b-1)*b)/2;
		R%=mod;
		long L = ((a*(a+1))/2)%mod;
		L = (L*R)%mod;
		L = (L*b)%mod;
		L += (a*R);
		L %=mod;

		System.out.println(L);
	}
	
	
    static BufferedReader reader = new BufferedReader(new InputStreamReader(
            System.in));
    static StringTokenizer tokenizer = new StringTokenizer("");

    static String next() throws IOException {
        while (!tokenizer.hasMoreTokens()) {
            String n = reader.readLine();
            if (n == null) {
                return null;
            }
            tokenizer = new StringTokenizer(n);

        }
        return tokenizer.nextToken();
    }

    static String nextLine() throws IOException {
        return reader.readLine();
    }

    static Integer nextInt() throws IOException {
        String next = next();
        if (next == null) {
            return null;
        }
        return Integer.parseInt(next);
    }

    static long nextLong() throws IOException {
        return Long.parseLong(next());
    }

    static Double nextDouble() throws IOException {
        return Double.parseDouble(next());
    }
    
    

}
