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