#include <bits/stdc++.h>
using namespace std;
const int oo = (int)1e9, MAXN = (int)1e4;
long long n, k, m;
long long safe[MAXN];
int main() {
  cin >> n >> m >> k;
  for (int i = 0; i < (n); i++) cin >> safe[i];
  if (n == 1)
    cout << min(safe[0], m * k) << endl;
  else if (n % 2 == 0)
    cout << 0 << endl;
  else {
    long long t = n / 2 + 1;
    long long perm = m / t;
    long long total = perm * k;
    long long maxvalue = oo;
    for (int i = 0; i < (n); i++) {
      maxvalue = min(maxvalue, safe[i]);
      i++;
    }
    cout << min(maxvalue, total) << endl;
  }
  return 0;
}
