#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  int a[n], b[n], c[n], d[n + 1], e[n + 1];
  d[0] = e[0] = 0;
  for (int i = 0; i < n - 1; i++) {
    cin >> a[i];
    if (i)
      d[i + 1] = d[i] + a[i];
    else
      d[i + 1] = a[i];
  }
  for (int i = 0; i < n - 1; i++) {
    cin >> b[i];
    e[i + 1] = e[i] + b[i];
  }
  for (int i = 0; i < n; i++) {
    cin >> c[i];
  }
  int sum = 0;
  int m1 = INT_MAX, m2 = INT_MAX;
  for (int i = n - 1; i >= 0; i--) {
    sum = c[i] + d[i];
    for (int j = n - 1; j > i; j--) sum += b[j - 1];
    if (sum < m1) {
      m2 = m1;
      m1 = sum;
    } else if (sum <= m2)
      m2 = sum;
  }
  cout << m1 + m2 << endl;
  return 0;
}
