#include <bits/stdc++.h>
using namespace std;
long long alm[10000];
int main() {
  long long n, m, k;
  cin >> n >> m >> k;
  for (int i = 0; i < n; i++) cin >> alm[i];
  if (n == 1) {
    long long res = min(alm[0], m * k);
    cout << res;
    return 0;
  } else if (n % 2 == 0) {
    cout << "0";
    return 0;
  } else {
    long long mini = 2000000000;
    for (int i = 0; i < n; i += 2) mini = min(mini, alm[i]);
    if (m < n / 2 + 1) {
      cout << "0";
      return 0;
    } else {
      long long res = (long long)k * (m / (n / 2 + 1));
      res = min(res, mini);
      cout << res;
      return 0;
    }
  }
  return 0;
}
