#include <bits/stdc++.h>
int ary[10010], min = 200000000;
int main(void) {
  int n, m, k;
  scanf("%d%d%d", &n, &m, &k);
  for (int i = 0; i < n; ++i) {
    scanf("%d", &ary[i]);
    if (i % 2 == 0) min = std::min(min, ary[i]);
  }
  if (n % 2 == 0)
    printf("0\n");
  else if (m < (n >> 1))
    printf("0\n");
  else {
    int t = (n >> 1) + 1;
    printf("%I64d\n", std::min((long long)m / t * k, (long long)min));
  }
  return 0;
}
