#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false), cin.tie(0);
  int n, a, b;
  cin >> n >> a >> b;
  int ans = 0;
  int c[n];
  for (int i = 0; i < n; i++) cin >> c[i];
  int st = 0;
  int en = n - 1;
  while (st <= en) {
    if (st == en) {
      if (c[st] == 2) {
        if (a < b) {
          c[st] = 0;
          ans += a;
        } else
          ans += b;
      }
    } else if (c[st] == c[en] && c[st] != 2) {
      st++, en--;
      continue;
    } else {
      if (c[st] == 2) {
        if (c[en] == 1)
          ans += b, c[st] = 1;
        else if (c[en] == 0)
          ans += a, c[st] = 0;
        else {
          if (a < b) {
            c[en] = 0;
            c[st] = 0;
            ans += 2 * a;
          } else {
            c[en] = 1;
            c[st] = 1;
            ans += 2 * b;
          }
        }
      } else if (c[en] == 2) {
        if (c[st] == 1)
          ans += b, c[en] = 1;
        else if (c[st] == 0)
          ans += a, c[en] = 0;
        else {
          if (a < b) {
            c[en] = 0;
            c[st] = 0;
            ans += 2 * a;
          } else {
            c[en] = 1;
            c[st] = 1;
            ans += 2 * b;
          }
        }
      }
    }
    st++;
    en--;
  }
  st = 0;
  en = n - 1;
  while (st <= en) {
    if (c[st] != c[en]) {
      cout << -1;
      return 0;
    }
    st++;
    en--;
  }
  cout << ans;
  return 0;
}
