#include<bits/stdc++.h>

using namespace std;

typedef unsigned long long ll;

const int mod = 1e9 + 7;

ll a,b;

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