#include <bits/stdc++.h>
using namespace std;
long long n, dia[10010], m, ans = 0, mis = 100000, k, need = 0;
int main() {
  cin >> n >> m >> k;
  for (int i = 1; i <= n; ++i) {
    cin >> dia[i];
    if (mis > dia[i] && i % 2 == 1) mis = dia[i];
  }
  need = n / 2 + 1;
  if (n % 2 == 0 || need > m)
    ;
  else {
    ans = m / need * k;
    ans = min(mis, ans);
  }
  cout << ans << endl;
  return 0;
}
