#include #define syosu(x) fixed< P; typedef pair pdd; typedef pair pll; typedef vector vi; typedef vector vvi; typedef vector vd; typedef vector vvd; typedef vector vl; typedef vector vvl; typedef vector vs; typedef vector

vp; typedef vector vvp; typedef vector vpll; typedef pair pip; typedef vector vip; const int inf=1<<30; const ll INF=1ll<<60; const double pi=acos(-1); const double eps=1e-9; const ll mod=1e9+7; const int dx[4]={0,1,0,-1},dy[4]={1,0,-1,0}; int n; vi a,b; int main(){ cin>>n; a=b=vi(n+1); for(auto &i:a) cin>>i; for(auto &i:b) cin>>i; ll t=0,S=0; for(int i=n;i>=0;i--){ (S+=b[n-i])%=mod; (t+=a[i]*S)%=mod; } cout<