#include <cstdio>
#include <cmath>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <vector>
#define Mod 1000000007
using namespace std;
typedef long long ll;
ll x,yy,xx,y;
//const int MAXN=1000000;
bool a[1000005]={false};
vector<int> ppn(){
vector<int> p;
p.push_back(2);
int i,j;
for(i=3;i*i<=1000005;i+=2){
if(!a[i]){
p.push_back(i);
for(j=i*i;j<=1000005;j+=i)
a[j]=true;
}
}
while(i<=1000005){
if(!a[i])
p.push_back(i);
i+=2;
}
return p;
}

int pr(int x, int p){
int s=0;
ll r=p;

while(x>=r){
s+=x/r;
r*=p;
}

return s;
}

int Pow(ll n,int k,int M){
ll s=1;
while(k){
if(k&1){
s=(s*n)%M;
}
n=(n*n)%M;
k>>=1;
}
return s;
}

int C(int n, int m){
const int M=1000000007;
vector<int> p=ppn();
ll s=1;
int nm;
for(unsigned int i=0;i<p.size() && p[i]<=n;++i){
nm=pr(n,p[i])-pr(m, p[i])-pr(n-m, p[i]);
s=(s*Pow(p[i],nm,M))%M;
}
return s;
}

ll c(ll x,ll y){
return C(x+y,x);

}
int main (){
cin>>x>>xx>>y>>yy;
ll a=c(x,y)%Mod,b=c(xx,yy)%Mod,d=c(x,yy)%Mod,e=c(xx,y)%Mod;
//printf ("%d %d %d %d\n",&a,&b,&c,&e);
ll s=(a*b-d*e)%Mod;
printf ("%I64d",s);
//while (1);
return 0;
}

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