#include <bits/stdc++.h>
const int magicconst = 73743071;
using namespace std;
const int maxn = 10050;
int a[maxn];
int main() {
  int n, m, k;
  scanf("%d%d%d", &n, &m, &k);
  if (n == 1) {
    int q;
    scanf("%d", &q);
    printf("%d\n", (int)min((long long)q, (long long)k * m));
    return 0;
  }
  if (n % 2 == 0) {
    printf("0");
    return 0;
  }
  int x;
  for (int i = 0; i < (int)(n); ++i) {
    scanf("%d", a + i);
  }
  long long res = 0;
  x = 100500;
  for (int i = 0; i < n; i += 2) x = min(x, a[i]);
  res = min((long long)x, (long long)k * (m / ((n + 1) / 2)));
  printf("%I64d\n", res);
  return 0;
}
