func_code_string: #include <bits/stdc++.h>   using namespace std;   long long i, j, k, n, a[100500][3], dp[100500][2];   int main() {     cin >> n;     for (j = 0; j < 3; j++)       for (i = 0; i < n; i++) cin >> a[i][j];     dp[0][0] = a[0][0];     dp[0][1] = a[0][1];     for (i = 1; i <= n; i++) {       dp[i][0] = max(dp[i - 1][0] + a[i][1], dp[i - 1][1] + a[i][0]);       dp[i][1] = max(dp[i - 1][0] + a[i][2], dp[i - 1][1] + a[i][1]);     }     cout << dp[n - 1][0] << endl;     return 0;   }   