Kertotaulu

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

ll mod=1e9+7;

ll ar(ll a){
    return ((a*(a+1ll))/2ll)%mod;
}

ll ar2(ll a, ll b){
    return (ar(a)*ar(b))%mod;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    ll y1,x1,y2,x2;
    cin>>y1>>x1>>y2>>x2;
    cout<<(ar2(y2, x2)-ar2(y1-1, x2)-ar2(y2, x1-1)+ar2(y1-1, x1-1)+mod*3ll)%mod<<endl;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED