#include <bits/stdc++.h>
using namespace std;
long long n, m, k;
const int MAXN = 10005;
long long a[MAXN];
long long solve(void) {
  if (n == 1) {
    return min(a[0], m * k);
  }
  if (n % 2 == 0) return 0;
  long long maxtr = a[0];
  for (int i = 0; i < n; i += 2) maxtr = min(maxtr, a[i]);
  long long forOne = (n / 2) + 1;
  long long canDo = k * (m / forOne);
  return min(maxtr, canDo);
}
int main() {
  cin >> n >> m >> k;
  for (int i = 0; i < n; i++) cin >> a[i];
  cout << solve();
  return 0;
}
