#include <bits/stdc++.h>
using namespace std;
int v[10003];
int n, m, k;
int main() {
  while (scanf("%d %d %d", &n, &m, &k) == 3) {
    for (int i = 0; i < n; i++) scanf("%d", v + i);
    if (n == 1) {
      printf("%d\n", (int)((long long int)m * (long long int)k < v[0]
                               ? (long long int)m * (long long int)k
                               : v[0]));
      continue;
    }
    if (n == 2 or m <= 1) {
      printf("0\n");
      continue;
    }
    if ((n % 2) == 0) {
      printf("0\n");
      continue;
    }
    if (m < (n + 1) / 2) {
      printf("0\n");
      continue;
    }
    int menorpar = 0x3f3f3f3f;
    for (int i = 0; i < n; i += 2)
      menorpar = (menorpar < v[i] ? menorpar : v[i]);
    int ops = (n + 1) / 2;
    long long int tot =
        (long long int)k * ((long long int)m / (long long int)ops);
    printf("%d\n", (int)(tot < menorpar ? tot : menorpar));
  }
  return 0;
}
