#include <iostream> #include <vector> #include <algorithm> using namespace std; int main() { int N; // 도시의 개수 long long expense = 0; // 총 요금 cin >> N; vector <long> distance(N - 1); // 다음 도시까지의 거리 vector <long> oil_fee(N); // 주유 요금 for(int i=0; i<N - 1; i++) { cin >> distance[i]; } for(int i=0; i<N; i++) { cin >> oil_fee[i]; } expense += distance[0] * oil_fee[0]; long long min_fee = oil_fee[0]; for(int i=1; i<N - 1; i++) { if(min_fee > oil_fee[i]) { min_fee = oil_fee[i]; } expense += distance[i] * min_fee; } cout << expense; return 0; }