#include <bits/stdc++.h>
#define endl '\n'
#define ld long double
#define pb push_back
#define pf push_front
#define mod 50000007
#define se second
#define fi first
#define all(ls) (ls).begin(),(ls).end()
#define int long long
using namespace std;
const int N=6e5+10;
int a[N],b[N];
int pre[N][100],suf[N][100],presum[N][100],sufsum[N][100];
void solve(){
int n;
cin>>n;
for(int i=1;i<=n;i++)
cin>>a[i];
for(int i=1;i<=n;i++)
cin>>b[i];
// if(n<=20){
// int ways=0;
// int p[n+10],s[n+10],cur[n+10];
// for(int mask=0;mask<(1<<n);mask++){
// for(int i=0;i<n;i++)
// if(mask&(1<<i))
// cur[i+1]=a[i+1];
// else
// cur[i+1]=b[i+1];
// p[0]=0;s[n+1]=0;
// for(int i=1;i<=n;i++)
// p[i]=max(p[i-1],cur[i]);
// for(int i=n;i>=1;i--){
// s[i]=max(s[i+1],cur[i]);
// ways=(ways+(min(p[i],s[i])-cur[i]))%mod;
// }
// }
// cout<<ways<<endl;
// return;
// }
pre[0][0]=1;
suf[n+1][0]=1;
for(int i=1;i<=n;i++){
for(int j=a[i]+1;j<=50;j++)
pre[i][j]=(pre[i][j]+pre[i-1][j])%mod;
for(int j=0;j<=a[i];j++)
pre[i][a[i]]=(pre[i][a[i]]+pre[i-1][j])%mod;
for(int j=b[i]+1;j<=50;j++)
pre[i][j]=(pre[i][j]+pre[i-1][j])%mod;
for(int j=0;j<=b[i];j++)
pre[i][b[i]]=(pre[i][b[i]]+pre[i-1][j])%mod;
for(int j=50;j>=0;j--)
presum[i][j]=(presum[i][j+1]+pre[i][j])%mod;
}
for(int i=n;i>=1;i--){
for(int j=a[i]+1;j<=50;j++)
suf[i][j]=(suf[i][j]+suf[i+1][j])%mod;
for(int j=0;j<=a[i];j++)
suf[i][a[i]]=(suf[i][a[i]]+suf[i+1][j])%mod;
for(int j=b[i]+1;j<=50;j++)
suf[i][j]=(suf[i][j]+suf[i+1][j])%mod;
for(int j=0;j<=b[i];j++)
suf[i][b[i]]=(suf[i][b[i]]+suf[i+1][j])%mod;
for(int j=50;j>=0;j--)
sufsum[i][j]=(sufsum[i][j+1]+suf[i][j])%mod;
}
// for(int i=1;i<=n;i++){
// for(int j=0;j<10;j++)
// cout<<pre[i][j]<<" ";
// cout<<endl;
// }
// cout<<endl;
// for(int i=1;i<=n;i++){
// for(int j=0;j<10;j++)
// cout<<suf[i][j]<<" ";
// cout<<endl;
// }
// cout<<endl;
// for(int i=1;i<=n;i++){
// for(int j=0;j<10;j++)
// cout<<presum[i][j]<<" ";
// cout<<endl;
// }
// cout<<endl;
// for(int i=1;i<=n;i++){
// for(int j=0;j<10;j++)
// cout<<sufsum[i][j]<<" ";
// cout<<endl;
// }
// cout<<endl;
int ways=0;
for(int i=1;i<=n;i++){
for(int j=a[i]+1;j<=50;j++){
ways=(ways+(((pre[i-1][j]*sufsum[i+1][j+1])%mod)*(j-a[i]))%mod)%mod;
ways=(ways+(((suf[i+1][j]*presum[i-1][j+1])%mod)*(j-a[i]))%mod)%mod;
ways=(ways+(((pre[i-1][j]*suf[i+1][j])%mod)*(j-a[i]))%mod)%mod;
}
for(int j=b[i]+1;j<=50;j++){
ways=(ways+(((pre[i-1][j]*sufsum[i+1][j+1])%mod)*(j-b[i]))%mod)%mod;
ways=(ways+(((suf[i+1][j]*presum[i-1][j+1])%mod)*(j-b[i]))%mod)%mod;
ways=(ways+(((pre[i-1][j]*suf[i+1][j])%mod)*(j-b[i]))%mod)%mod;
}
}
cout<<ways<<endl;
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t=1;
// cin>>t;
for(int i=1;i<=t;i++){
// cout<<"Scenario #"<<i<<":"<<" ";
solve();
}
}
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