# include<iostream> # include<cstdio> using namespace std; int main() { int n,m,r = 0; cin>>n; int a[n],b[n]; for(int i = 0; i < n; i++) { cin>>m; a[i] = m; } for(int i = 0; i < n; i++) { cin>>m; b[i] = m; } for(int i = 0; i < n; i++) { r += a[i]*b[i]; } printf("\n%d", r); return 0; }