#include <bits/stdc++.h>

using namespace std;

using ll = long long;

const int MOD = 1e9 + 7;

int main(void) {
  ll A, B;
  scanf("%lld %lld", &A, &B);

  A %= MOD;
  B %= MOD;

  if (A % 2 == B % 2) printf("%lld\n", (2 * A % MOD * B % MOD + (A + B) % MOD + 1) % MOD);
  else printf("%lld\n", (2 * A % MOD * B % MOD + (A + B) % MOD) % MOD);

  return 0;
}