#include <bits/stdc++.h>
using namespace std;
int a[10005];
int main(void) {
  int n, m, k;
  scanf("%d%d%d", &n, &m, &k);
  for (int i = 0; i < n; i++) scanf("%d", &a[i]);
  if (n == 1) {
    printf("%I64d\n", min(a[0] * 1LL, m * 1LL * k));
    return 0;
  }
  if (n % 2 == 0 || m < (n + 1) / 2) {
    puts("0");
    return 0;
  }
  long long r = (m / ((n + 1) / 2) * 1LL * k);
  for (int i = 0; i < n; i += 2) r = min(r, 1LL * a[i]);
  printf("%I64d\n", r);
  return 0;
}
