#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

const int mod = 1e9 + 7;

ll a,b;

int main()
{
    scanf("%lld %lld",&a,&b);
    ll ans = 0;
    ans += (2ll * a % mod * b % mod) % mod + a % mod + b % mod + 1ll;;
    ans %= mod;
    if(a - b & 1ll) ans -= 1ll;
    printf("%lld\n",ans % mod);
    return 0;
}