func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, a, b;     cin >> n >> a >> b;     int position[21] = {0};     for (int i = 0; i < n; i++) cin >> position[i];     int head = 0, tail = n - 1, cost = 0;     while (head <= tail) {       if (position[head] != 2 && position[tail] != 2 &&           (position[head] != position[tail])) {         cost = -1;         break;       }       if (position[head] == 2 && position[tail] == 2 && head != tail) {         if (a > b)           cost += 2 * b;         else           cost += 2 * a;       } else if (position[head] == 2 && position[tail] == 2 && head == tail) {         if (a > b)           cost += b;         else           cost += a;       } else if (position[head] == 2 || position[tail] == 2) {         if (position[head] == 2 && position[tail] == 0)           cost += a;         else if (position[head] == 2 && position[tail] == 1)           cost += b;         else if (position[tail] == 2 && position[head] == 0)           cost += a;         else if (position[tail] == 2 && position[head] == 1)           cost += b;       }       head++;       tail--;     }     cout << cost;     return 0;   }   