#include <bits/stdc++.h>
using namespace std;
int n;
int dist[2][50];
int across[50];
int crossed = 0;
int dp[2][50];
int total = 0;
void rundp() {
  dp[0][0] = 0;
  dp[1][0] = across[0];
  for (int i = 1; i < n; i++) {
    dp[0][i] = dp[0][i - 1] + dist[0][i - 1];
    dp[1][i] = dp[1][i - 1] + dist[1][i - 1];
    if (dp[0][i] + across[i] < dp[1][i]) {
      dp[1][i] = dp[0][i] + across[i];
      crossed = i;
    }
  }
}
int main() {
  cin >> n;
  for (int i = 0; i < 2; i++) {
    for (int x = 0; x < n - 1; x++) {
      cin >> dist[i][x];
    }
  }
  for (int i = 0; i < n; i++) {
    cin >> across[i];
  }
  rundp();
  total = dp[1][n - 1];
  across[crossed] = 10000000;
  rundp();
  total += dp[1][n - 1];
  cout << total << endl;
}
