#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e4 + 5;
int n, m, k;
int a[maxn];
int main() {
  cin.tie(0), ios_base::sync_with_stdio(false);
  cin >> n >> m >> k;
  for (int i = 0; i < n; ++i) cin >> a[i];
  if (n % 2 == 0) {
    cout << 0 << endl;
    return 0;
  }
  int mx = a[0];
  for (int i = 0; i < n; ++i)
    if (i % 2 == 0) mx = min(mx, a[i]);
  long long int ans = k;
  long long int c = n / 2 + 1;
  ans *= m / c;
  if (m < c) ans = 0;
  cout << min(ans, (long long int)mx) << endl;
  return 0;
}
