#include <bits/stdc++.h>
using namespace std;
int a[10010];
int n, m, k;
int main() {
  int i, j;
  int res;
  while (scanf("%d%d%d", &n, &m, &k) != EOF) {
    for (i = 1; i <= n; i++) {
      scanf("%d", &a[i]);
    }
    if (n % 2 == 0 || m < n / 2 + 1) {
      printf("0\n");
      continue;
    }
    long long now = k;
    now *= m / (n / 2 + 1);
    int minn = a[1];
    for (i = 1; i <= n; i += 2) {
      minn = min(minn, a[i]);
    }
    res = min((long long)minn, now);
    printf("%d\n", res);
  }
  return 0;
}
