#include <bits/stdc++.h>
using namespace std;
const int inf = 1 << 28;
const double INF = 1e12, EPS = 1e-9;
int n, m, k, a[10000];
void run() {
  cin >> n >> m >> k;
  for (int i = 0; i < n; i++) cin >> a[i];
  int move = n / 2 + 1;
  if (n % 2 == 0 || move > m) {
    cout << 0 << endl;
    return;
  }
  int times = inf;
  for (int i = 0; i < n; i += 2) times = min(times, a[i]);
  int moveperset = m / move;
  times = min((long long)times, (long long)moveperset * k);
  cout << times << endl;
}
int main() { run(); }
