package jp.fedom.challange.yuki.q146; import java.math.BigInteger; import java.util.Scanner; public class Main { static BigInteger t = BigInteger.ZERO; static BigInteger m = new BigInteger("1000000007"); public static void main(String[] args) { Scanner sc = new Scanner(System.in); while (sc.hasNext()) { solve(sc.nextLine()); } t = t.mod(m); System.out.println(t.toString()); sc.close(); } public static void solve(String input) { if (input.split(" ").length == 1) { input = null; return; } String[] ss = input.split(" "); long s = Long.valueOf(ss[0]); long k = Long.valueOf(ss[1]); input = null; if (s % 2 == 0) { t = t.add(new BigInteger(String.valueOf((s / 2) * k))); } else { t = t.add(new BigInteger(String.valueOf((s + 1) / 2 * k))); } } }