a,b= map(int, input().split())
x=int((1e9)+7)
z=(b*(b-1))//2
z=z*a
z=z*(2+ (b*(a+1)))
z=z//2
print(z%x)#include<bits/stdc++.h>
using namespace std;
#define int long long
int mod=1e9+7;
signed main(){
int a,b;
cin>>a>>b;
int sum1=(((b*(b-1)/2)%mod)*((a*(a+1)/2)%mod))%mod*b;
int sum2=((b*(b-1)/2)%mod)*a;
cout<<(sum1%mod+sum2%mod)%mod<<endl;
}
Duration | Birthday Party |
e-maze-in | Bricks Game |
Char Sum | Two Strings |
Anagrams | Prime Number |
Lexical Sorting Reloaded | 1514A - Perfectly Imperfect Array |
580A- Kefa and First Steps | 1472B- Fair Division |
996A - Hit the Lottery | MSNSADM1 Football |
MATCHES Playing with Matches | HRDSEQ Hard Sequence |
DRCHEF Doctor Chef | 559. Maximum Depth of N-ary Tree |
821. Shortest Distance to a Character | 1441. Build an Array With Stack Operations |
1356. Sort Integers by The Number of 1 Bits | 922. Sort Array By Parity II |
344. Reverse String | 1047. Remove All Adjacent Duplicates In String |
977. Squares of a Sorted Array | 852. Peak Index in a Mountain Array |
461. Hamming Distance | 1748. Sum of Unique Elements |
897. Increasing Order Search Tree | 905. Sort Array By Parity |