#include<bits/stdc++.h> using namespace std; int main(){ int n; cin>>n; int a[n];//0,1,2...,n-1 //a[5] 0,1,2,3,4 //b[6] 0,1,2,3,4,5 int b[n]; for(int i=0;i<=n-1;i++){ cin>>a[i]; } for(int i=0;i<=n-1;i++){ cin>>b[i]; } int sum=0; for(int i=0;i<=n-1;i++){ sum=sum+a[i]*b[i]; } cout<<sum; return 0; }