#include <bits/stdc++.h>
using namespace std;
int fw[10000];
int bw[10000];
int main() {
  int n;
  cin >> n;
  for (int i = 2; i <= n; i++) {
    int a;
    cin >> a;
    fw[i] = fw[i - 1] + a;
  }
  for (int i = 2; i <= n; i++) {
    int a;
    cin >> bw[i];
  }
  for (int i = n; i >= 2; i--) {
    bw[i] = bw[i + 1] + bw[i];
  }
  int cross[10000];
  for (int i = 1; i <= n; i++) cin >> cross[i];
  int best = INT_MAX;
  int sbest = INT_MAX;
  for (int i = n; i >= 1; i--) {
    if (best > bw[i + 1] + cross[i] + fw[i]) {
      sbest = best;
      best = bw[i + 1] + cross[i] + fw[i];
    } else if (sbest > bw[i + 1] + cross[i] + fw[i])
      sbest = bw[i + 1] + cross[i] + fw[i];
  }
  cout << best + sbest << endl;
}
