#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n, m, k, temp, index1 = -1, index2, Min = 100000000000000000;
  cin >> n >> k >> m;
  for (int i = 0; i < n; i++) {
    cin >> temp;
    if (i % 2 == 0 && index1 == -1) index1 = i;
    if (i % 2 == 0) index2 = i;
    if (i % 2 == 0) Min = min(Min, temp);
  }
  if (n % 2 == 0 || n / 2 + 1 > k || (index2 - index1) % 2) {
    cout << 0 << endl;
    return 0;
  }
  cout << min(Min, (k / (n / 2 + 1)) * m) << endl;
  return 0;
}
