# include<iostream> using namespace std; int main(){ int z[1001],n,a[1001],s=0; cin>>n; for(int i=0;i<n;i++){ cin>>z[i];} for(int i=0;i<n;i++){ cin>>a[i]; } for(int i=0;i<n;i++){ s+=z[i]*a[i];} cout<<s; return 0;}